U.S. patent application number 17/124506 was filed with the patent office on 2021-11-18 for production apparatus and method for electric arc furnace steelmaking with fully continuous ultra-short process.
This patent application is currently assigned to University of Science and Technology Beijing. The applicant listed for this patent is University of Science and Technology Beijing. Invention is credited to Kai DONG, Rongfang SU, Bohan TIAN, Guangsheng WEI, Rong ZHU.
Application Number | 20210355554 17/124506 |
Document ID | / |
Family ID | 1000005941030 |
Filed Date | 2021-11-18 |
United States Patent
Application |
20210355554 |
Kind Code |
A1 |
ZHU; Rong ; et al. |
November 18, 2021 |
PRODUCTION APPARATUS AND METHOD FOR ELECTRIC ARC FURNACE
STEELMAKING WITH FULLY CONTINUOUS ULTRA-SHORT PROCESS
Abstract
A production apparatus and method for electric arc furnace
steelmaking with a fully continuous ultra-short process are
provided. A continuous adding, melting, smelting and continuous
casting of a metal material are integrated, and a metallurgy
process is completed in a flowing of a molten steel, to realize a
continuous production of ingot blanks. The production apparatus
includes four operation sites of an electric arc furnace for
melting and primary refining, a sealed tapping chute for molten
steel flowing, a refinement storage bed for molten-steel
desulfurization and alloying and a conticaster for continuous
casting A material flow, an energy flow and a time stream in the
four operation sites are in a dynamic equilibrium. The production
apparatus and method realize a molten-steel casting is started
within 120 minutes after the metal material is started to be
continuously added, and an uninterrupted continuous production is
maintained for above 80 hours.
Inventors: |
ZHU; Rong; (Beijing, CN)
; TIAN; Bohan; (Beijing, CN) ; DONG; Kai;
(Beijing, CN) ; WEI; Guangsheng; (Beijing, CN)
; SU; Rongfang; (Beijing, CN) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
University of Science and Technology Beijing |
Beijing |
|
CN |
|
|
Assignee: |
University of Science and
Technology Beijing
Beijing
CN
|
Family ID: |
1000005941030 |
Appl. No.: |
17/124506 |
Filed: |
December 17, 2020 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
F27B 3/19 20130101; F27B
3/085 20130101; C21B 13/125 20130101 |
International
Class: |
C21B 13/12 20060101
C21B013/12; F27B 3/19 20060101 F27B003/19 |
Foreign Application Data
Date |
Code |
Application Number |
May 14, 2020 |
CN |
202010406632.3 |
Claims
1. A production apparatus for an electric arc furnace steelmaking
with a fully continuous process, comprising four operation sites,
wherein the four operation sites are an electric arc furnace for
melting and primary refining, a sealed tapping chute for molten
steel flows out of the electric arc furnace, a refinement storage
bed for molten-steel desulfurization and alloying and a conticaster
for continuous casting; a material flow, an energy flow and a time
stream in the four operation sites are in a dynamic equilibrium;
the electric arc furnace, the refinement storage bed and the
conticaster are arranged from a higher position to a lower position
respectively, a tapping hole of the electric arc furnace located at
a higher position is connected to a higher-position end of the
refinement storage bed located at a lower position via the sealed
tapping chute, and the conticaster is located below a
lower-position end of the refinement storage bed, and the
conticaster is connected via the tapping hole; sizes of the
electric arc furnace, the sealed tapping chute, the refinement
storage bed and the conticaster are matched; materials, energies,
times and temperatures in the electric arc furnace, the sealed
tapping chute, the refinement storage bed and the conticaster are
matched and dynamically linked; the electric arc furnace, the
sealed tapping chute, the refinement storage bed and the
conticaster are arranged from a higher position to a lower position
spatially; after a smelting is started, a metal material is
continuously added into the electric arc furnace, to complete the
melting and a dephosphorization; a carbon powder and a silicon
powder are jetted into the sealed tapping chute as reducing-agent
powders; and refining is performed at the higher-position end of
the refinement storage bed, to complete the desulfurization and
alloying, and a refined molten steel is stored and heated at the
lower-position end of the refinement storage bed, and the refined
molten steel continuously flows into the conticaster, to obtain an
ingot blank, to realize a fully continuous steelmaking, wherein the
electric arc furnace comprises a continuously feeding device, a
furnace door, a furnace-wall coherent oxygen lance, electrodes, a
tapping mechanism and a temperature measuring and sampling device;
the continuously feeding device is a shaft or a horizontal
continuously feeding device; the furnace door is located at a
furnace wall of the electric arc furnace, and the furnace door
discharges a slag in a smelting process; the furnace-wall coherent
oxygen lance is installed at a suitable position of a side wall of
the electric arc furnace, and wherein the furnace-wall coherent
oxygen lance has a function of blowing flux into the metal material
to form the slag; the electrodes are inserted into the electric arc
furnace via a top end of the electric arc furnace; wherein the
tapping mechanism is configured as a siphoning unit, so as to
achieve a slag-free tapping; and the temperature measuring and
sampling device is located over a tapping hole of the tapping
mechanism, and the temperature measuring and sampling device
monitors a temperature and components of a tapped molten steel in
real time.
2. (canceled)
3. A production apparatus for an electric arc furnace steelmaking
with a fully continuous process, comprising four operation sites,
wherein the four operation sites are an electric arc furnace for
melting and primary refining, a sealed tapping chute for molten
steel flows out of the electric arc furnace, a refinement storage
bed for molten-steel desulfurization and alloying and a conticaster
for continuous casting; a material flow, an energy flow and a time
stream in the four operation sites are in a dynamic equilibrium;
the electric arc furnace, the refinement storage bed and the
conticaster are arranged from a higher position to a lower position
respectively, a tapping hole of the electric arc furnace located at
a higher position is connected to a higher-position end of the
refinement storage bed located at a lower position via the sealed
tapping chute, and the conticaster is located below a
lower-position end of the refinement storage bed, and the
conticaster is connected via the tapping hole; sizes of the
electric arc furnace, the sealed tapping chute, the refinement
storage bed and the conticaster are matched; materials, energies,
times and temperatures in the electric arc furnace, the sealed
tapping chute, the refinement storage bed and the conticaster are
matched and dynamically linked; the electric arc furnace, the
sealed tapping chute, the refinement storage bed and the
conticaster are arranged from a higher position to a lower position
spatially; after a smelting is started, a metal material is
continuously added into the electric arc furnace, to complete the
melting and a dephosphorization; a carbon powder and a silicon
powder are jetted into the sealed tapping chute as reducing-agent
powders; and refining is performed at the higher-position end of
the refinement storage bed, to complete the desulfurization and
alloying, and a refined molten steel is stored and heated at the
lower-position end of the refinement storage bed, and the refined
molten steel continuously flows into the conticaster, to obtain an
ingot blank, to realize a fully continuous steelmaking, wherein the
sealed tapping chute is of a sealed structure, and the sealed
tapping chute comprises a chute main body, an upper through hole, a
powder jetting device and a lower through hole; the chute main body
is constructed by using a refractory material; the upper through
hole is a molten-steel flow-in end, and the upper through hole is
connected to the tapping hole of the electric arc furnace; the
powder jetting device is inserted into the chute main body, and the
powder jetting device jets the carbon powder and the silicon powder
as the reducing-agent powders to a steel flow; and the lower
through hole is a molten-steel flow-out end, and the lower through
hole is connected to the refinement storage bed, and the lower
through hole protrudes below a liquid level of the refined molten
steel in the refinement storage bed.
4. A production apparatus for an electric arc furnace steelmaking
with a fully continuous process, comprising four operation sites,
wherein the four operation sites are an electric arc furnace for
melting and primary refining, a sealed tapping chute for molten
steel flows out of the electric arc furnace, a refinement storage
bed for molten-steel desulfurization and alloying and a conticaster
for continuous casting; a material flow, an energy flow and a time
stream in the four operation sites are in a dynamic equilibrium;
the electric arc furnace, the refinement storage bed and the
conticaster are arranged from a higher position to a lower position
respectively, a tapping hole of the electric arc furnace located at
a higher position is connected to a higher-position end of the
refinement storage bed located at a lower position via the sealed
tapping chute, and the conticaster is located below a
lower-position end of the refinement storage bed, and the
conticaster is connected via the tapping hole; sizes of the
electric arc furnace, the sealed tapping chute, the refinement
storage bed and the conticaster are matched; materials, energies,
times and temperatures in the electric arc furnace, the sealed
tapping chute, the refinement storage bed and the conticaster are
matched and dynamically linked; the electric arc furnace, the
sealed tapping chute, the refinement storage bed and the
conticaster are arranged from a higher position to a lower position
spatially; after a smelting is started, a metal material is
continuously added into the electric arc furnace, to complete the
melting and a dephosphorization; a carbon powder and a silicon
powder are jetted into the sealed tapping chute as reducing-agent
powders; and refining is performed at the higher-position end of
the refinement storage bed, to complete the desulfurization and
alloying, and a refined molten steel is stored and heated at the
lower-position end of the refinement storage bed, and the refined
molten steel continuously flows into the conticaster, to obtain an
ingot blank, to realize a fully continuous steelmaking, wherein the
refinement storage bed is of a sealed structure, and the refinement
storage bed comprises a bottom-blowing element, a charging hole, a
flue, a vacuum slag cleaner, an induction coil, a plasma gun, a
tapping linking device, a tapping hole and a slag hole; the
refinement storage bed is constructed by using a refractory
material, wherein the refinement storage bed is arranged in a form
of a vertical step, and the refinement storage bed has a first end
connected to the sealed tapping chute as the higher-position end,
and a second end connected to the conticaster as the lower-position
end; the bottom-blowing element is at a bottom of the refinement
storage bed; the charging hole is arranged at a top of the
refinement storage bed; or the temperature measuring and sampling
device or a charging tube protrudes into the refinement storage bed
via the charging hole; the flue is located at the top of the
refinement storage bed; the vacuum slag cleaner is located behind a
last charging hole at an end adjacent to the conticaster of the top
of the refinement storage bed, and contacts a slag surface; the
induction coil and/or the plasma gun are arranged at a bed wall of
the refinement storage bed; the tapping linking device located at
the lower-position end of the refinement storage bed stores an
amount of the refined molten steel, and the tapping linking device
has a cushioning effect, wherein a slag dam is provided at a
connection between the tapping linking device and the
higher-position end of the refinement storage bed, and the slag dam
a slag-free tapping; the tapping hole of the refinement storage bed
is located at an end of the bottom of the refinement storage bed,
wherein the end of the bottom of the refinement storage bed is
adjacent to the conticaster, and the tapping hole of the refinement
storage bed is connected to the conticaster; and the slag hole is
an opening at a furnace wall of the refinement storage bed.
5. A production method for the electric arc furnace steelmaking
with the fully continuous process by using the production apparatus
according to claim 1, comprising in a smelting process, adding the
metal material by a continuously feeding device into the electric
arc furnace, and melting and primarily refining to become a molten
steel; the molten steel entering and flowing in the sealed tapping
chute; the molten steel flowing into the refinement storage bed,
and undergoing the molten-steel desulfurization and alloying, to
reach a qualified temperature and components; the refined molten
steel flowing into the conticaster, and undergoing the continuous
casting, to finally obtain a qualified ingot blank; and in the
smelting process, in the electric arc furnace, by blowing oxygen
and supplying electricity by using a furnace-wall coherent oxygen
lance and electrodes, melting the metal material and heating, and
in the refinement storage bed, heating the molten steel by using an
induction coil and/or a plasma gun.
6. The production method according to claim 5, comprising by using
the production apparatus for the electric arc furnace steelmaking
with the fully continuous process, continuously adding the metal
material into the electric arc furnace, to complete the melting and
the dephosphorization; jetting the carbon powder and the silicon
powder into the sealed tapping chute as the reducing-agent powders;
refining at the higher-position end of the refinement storage bed,
to complete the desulfurization and alloying, and the refined
molten steel being stored and heated at the lower-position end of
the refinement storage bed, and the refined molten steel
continuously flowing into the conticaster, to form the ingot blank,
to realize the fully continuous steelmaking; and a detailed process
is as follows: T0-T1 stage: wherein the metal material is
continuously added into the electric arc furnace; T1-T2 stage:
wherein the metal material melts in the electric arc furnace into
the molten steel, completes an oxidative dephosphorization, and the
molten steel flows into the sealed tapping chute; T2-T3 stage:
wherein the molten steel is deoxidized in the sealed tapping chute
and the molten steel flows to the refinement storage bed; T3-T4
stage: wherein the molten steel flows in the higher-position end of
the refinement storage bed, undergoes refinement, and the molten
steel completes the desulfurization and alloying; and T4-T5 stage:
wherein the refined molten steel enters the lower-position end of
the refinement storage bed, and the refined molten steel is
injected into a crystallizer of the conticaster to form the ingot
blank.
7. The production method according to claim 6, wherein a duration
of the T0-T1 stage is controlled within 5-10 min; a duration of the
T1-T2 stage is controlled within 20-50 min; a duration of the T2-T3
stage is controlled within 5-10 min; a duration of the T3-T4 stage
is controlled within 20-50 min; and a duration of the T4-T5 stage
is controlled within 5-20 min.
8. The production method according to claim 6, wherein in the T0-T1
stage, the detailed process is: adding the metal material into the
electric arc furnace by using the continuously feeding device; in
the T1-T2 stage, the detailed process is: the electrodes
descending, and electrified to melt the metal material, turning on
the furnace-wall coherent oxygen lance to flux or form the slag to
assist in the smelting, a furnace door automatically discharging
the slag, measuring the temperature and components of the molten
steel by using a temperature measuring and sampling device at a
tapping area of the electric arc furnace, turning on a tapping
mechanism to tap, and the molten steel flowing into the sealed
tapping chute; in the T2-T3 stage, the detailed process is: the
molten steel flowing in the sealed tapping chute, and according to
the temperature and components of the molten steel at the tapping
area of the electric arc furnace, jetting the carbon powder and the
silicon powder as the reducing-agent powders to a steel flow by
using a powder jetting device; in the T3-T4 stage, the detailed
process is: performing an argon blowing and stirring by using a
bottom-blowing element; by using a charging hole, measuring the
temperature of the molten steel and adding a smelting auxiliary
material, and according to a particular condition of the molten
steel, performing a different feeding operation at a next charging
hole; heating and stirring the molten steel by using the induction
coil and/or the plasma gun, and heating the molten steel and
homogenizing the temperature and components; and automatically
removing a molten slag by using a vacuum slag cleaner or a slag
hole; and in the T4-T5 stage, the detailed process is: controlling
the molten steel to reach a predetermined standard of the
temperature and components, and feeding the molten steel into the
crystallizer of the conticaster to form the ingot blank.
9. The production method according to claim 6, comprising when the
smelting is started, filling up the electric arc furnace with the
metal material, and after the metal material in the electric arc
furnace has completely melted into the molten steel, opening the
tapping mechanism and maintaining an opened state; the molten steel
increasingly flowing into the refinement storage bed via the sealed
tapping chute, performing the refinement, removing in time the
molten slag by using a vacuum slag cleaner or a slag hole to
prevent a molten slag from entering the lower-position end of the
refinement storage bed, and when a tapping linking device of the
refinement storage bed is full of the molten steel, opening the
tapping hole and maintaining the opened state; a finished molten
steel continuously flowing into the conticaster via the tapping
hole, to obtain a finished steel billet; and subsequently realizing
an uninterrupted production of the ingot blank from the finished
molten steel.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is based upon and claims priority to
Chinese Patent Application No. 202010406632.3, filed on May 14,
2020, the entire contents of which are incorporated herein by
reference.
TECHNICAL FIELD
[0002] The present disclosure relates to the technical field of
steelmaking, and particularly relates to a production apparatus and
method for electric arc furnace steelmaking with a fully continuous
ultra-short process.
BACKGROUND
[0003] Currently, the production from a metal material to ingot
blanks mainly relies on electric arc furnace steelmaking systems.
Such a system has three working procedures of electric arc furnace
steelmaking, refinement and continuous casting. Modern electric arc
furnace steelmaking systems realize the continuous production of
ingot blanks by using a continuous-casting apparatus. However, the
smelting and transportation are still a process of opened
intermittent production, wherein the temperature loss of the molten
steel is considerable, and the time waste between the working
procedures is serious.
[0004] Smelting production apparatuses such as electric arc
furnaces and ladle furnaces have different operation approaches at
different stages of smelting. However, because the condition inside
the furnaces is complicated, that cannot be accurately determined,
and the operation mainly relies on the experience of the workers,
which results in a high operation error and instable production.
Moreover, the conditions inside the furnace at different stages of
smelting are different, and the temperature and the components vary
largely, and are distributed non-uniformly inside the furnace,
which results in the problems such as serious erosion of the
refractory materials and superheat damage of the apparatus, and
affects the life of the furnace body.
[0005] The electric arc furnace steelmaking systems employ
intermitted and discontinuous ladles that sequentially enter the
production operation sites, and finally perform the continuous
production of ingot blanks by using a continuous-casting apparatus.
The ladle transferring process inevitably generates the conditions
such as un-smooth linking between the working procedures, ladle to
ladle, and exposure to air of the molten steel, which results in
the problems such as a large temperature fall in the molten steel
and a high contents of [N] and [H] in the molten steel, and results
in high electricity-power consumption and material consumption of
the smelting, a low production efficiency, a poor product quality
and a high production cost.
SUMMARY
[0006] An object of the present disclosure is to overcome the
disadvantages of the current apparatuses and processes for electric
arc furnace steelmaking systems, by providing a production
apparatus and method for electric arc furnace steelmaking with a
fully continuous ultra-short process having good stability and
efficiency, a low cost, a high quality and a long life, which can
realize stable production, shorten the tap-to-tap period of the
product, reduce the energy consumption and the material consumption
of the smelting, improve the quality of products, and prolong the
equipment life.
[0007] A production apparatus for electric arc furnace steelmaking
with a fully continuous ultra-short process, wherein the production
apparatus comprises four operation sites of an electric arc
furnace, a sealed tapping chute, a refinement storage bed and a
conticaster, respectively for melting and primary refining, molten
steel flowing, molten-steel desulfurization and alloying, and
continuous casting;
[0008] material flow, energy flow and time stream in the operation
sites are in dynamic equilibrium;
[0009] the electric arc furnace, the refinement storage bed and the
conticaster are arranged from higher to lower, a tapping hole of
the electric arc furnace located at a higher position is connected
to a higher-position end of the refinement storage bed located at a
lower position via the sealed tapping chute, and the conticaster is
located below a lower-position end of the refinement storage bed,
and is connected via the tapping hole;
[0010] sizes of the electric arc furnace, the sealed tapping chute,
the refinement storage bed and the conticaster are matched;
[0011] materials, energies, times and temperatures in the electric
arc furnace, the sealed tapping chute, the refinement storage bed
and the conticaster are matched and dynamically linked;
[0012] the electric arc furnace, the sealed tapping chute, the
refinement storage bed and the conticaster are arranged from higher
to lower in space;
[0013] after the smelting is started, a metal material is
continuously added into the electric arc furnace, to complete
melting and dephosphorization;
[0014] a carbon powder and a silicon powder are jetted into the
sealed tapping chute as reducing-agent powders; and
[0015] refining is performed at the higher-position end of the
refinement storage bed, to complete desulfurization and alloying,
and the molten steel that has been refined is stored and heated at
the lower-position end of the refinement storage bed, and
continuously flows into the conticaster, to obtain an ingot blank,
to realize fully continuous steelmaking.
[0016] The present disclosure can realize that the molten-steel
casting is started within the 120 minutes after the metal material
is started to be continuously added, and the uninterrupted
continuous production is maintained for above 80 hours, which
reduces the loss in the energy and the time in the smelting
process. By using the present disclosure, the output is increased
by above 20% as compared with conventional processes, and the
contents of the harmful elements in the ingot blanks such as [P],
[S], [O], [N] and [H] satisfy the requirements on high-quality
steel products. Regarding one ton of the steel, the
electricity-power consumption is reduced by 50 kWh, and the energy
consumption is reduced by above 20 kgce.
[0017] Optionally, the electric arc furnace comprises a
continuously feeding device, a furnace door, a furnace-wall
coherent oxygen lance, electrodes, a tapping mechanism and a
temperature measuring and sampling device;
[0018] the continuously feeding device is a shaft or horizontal
continuously feeding device;
[0019] the furnace door is located at a furnace wall of the
electric arc furnace, and is able to discharge slag in the smelting
process;
[0020] the furnace-wall coherent oxygen lance is installed at a
suitable position of a side wall of the electric arc furnace, and
functions to flux the metal material, blow and form slag;
[0021] the electrodes are inserted into the electric arc furnace
via a top end of the electric arc furnace;
[0022] the tapping mechanism employs a principle of siphon, and is
able to realize slag-free tapping; and
[0023] the temperature measuring and sampling device is located
over a tapping hole of the tapping mechanism, and is able to
monitor in real time a temperature and components of tapped molten
steel.
[0024] Optionally, the sealed tapping chute is of a sealed
structure, and comprises a chute main body, an upper through hole,
a powder jetting device and a lower through hole;
[0025] the chute main body is constructed by using a refractory
material;
[0026] the upper through hole is a molten-steel flow-in end, and is
connected to the tapping hole of the electric arc furnace;
[0027] the powder jetting device is inserted into the chute main
body, and jets the carbon powder and the silicon powder as the
reducing-agent powders to a steel flow; and
[0028] the lower through hole is a molten-steel flow-out end, and
is connected to the refinement storage bed, and the lower through
hole protrudes below a liquid level of the molten steel in the
refinement storage bed.
[0029] Optionally, the refinement storage bed is of a sealed
structure, and comprises a bottom-blowing element, a charging hole,
a flue, a vacuum slag cleaner, an induction coil, a plasma gun, a
tapping linking device, a tapping hole and a slag hole;
[0030] the refinement storage bed is constructed by using a
refractory material, is arranged in a form of a vertical step, and
has one end connected to the sealed tapping chute as the
higher-position end, and one end connected to the conticaster as
the lower-position end;
[0031] the bottom-blowing element is at a bottom of the refinement
storage bed;
[0032] the charging hole is arranged at a top of the refinement
storage bed; or
[0033] the temperature measuring and sampling device or a charging
tube protrudes into the refinement storage bed via the charging
hole;
[0034] the flue is located at a top of the refinement storage
bed;
[0035] the vacuum slag cleaner is located behind a last one
charging hole at one end adjacent to the conticaster of a top of
the refinement storage bed, and contacts a slag surface;
[0036] the induction coil and/or the plasma gun are arranged at a
bed wall of the refinement storage bed;
[0037] the tapping linking device is located at the lower-position
end of the refinement storage bed, is able to store an amount of
molten steel, and has a cushioning effect, wherein a slag dam is
provided at a connection between the tapping linking device and the
higher-position end of the refinement storage bed, and is able to
realize slag-free tapping;
[0038] the tapping hole is located at one end of a bottom of the
refinement storage bed that is adjacent to the conticaster, and is
connected to the conticaster; and
[0039] the slag hole is an opening at a furnace wall of the
refinement storage bed.
[0040] The present disclosure further provides a production method
for electric arc furnace steelmaking with a fully continuous
ultra-short process, by using the production apparatus for electric
arc furnace steelmaking with a fully continuous ultra-short
process, wherein the production method comprises, in a smelting
process, adding a metal material by the continuously feeding device
into the electric arc furnace, and melting and primarily refining
to become molten steel;
[0041] the molten steel entering and flowing in the sealed tapping
chute;
[0042] the molten steel flowing into the refinement storage bed,
and undergoing molten-steel desulfurization and alloying, to reach
qualified temperature and components;
[0043] the molten steel that has been refined flowing into the
conticaster, and undergoing continuous casting, to finally obtain a
qualified ingot blank; and
[0044] in the smelting process, in the electric arc furnace, by
blowing oxygen and supplying electricity by using the furnace-wall
coherent oxygen lance and the electrodes, melting the metal
material and heating, and in the refinement storage bed, heating
the molten steel by using the induction coil and/or the plasma
gun.
[0045] Optionally, the production method comprises, by using the
production apparatus for electric arc furnace steelmaking with a
fully continuous ultra-short process, continuously adding the metal
material into the electric arc furnace, to complete melting and
dephosphorization;
[0046] jetting a carbon powder and a silicon powder into the sealed
tapping chute as reducing-agent powders;
[0047] refining at the higher-position end of the refinement
storage bed, to complete desulfurization and alloying, and the
molten steel that has been refined being stored and heated at the
lower-position end of the refinement storage bed, and continuously
flowing into the conticaster, to form an ingot blank, to realize
fully continuous steelmaking; and
[0048] the detailed process is as follows:
[0049] T0-T1 stage: a stage in which the metal material is
continuously added into the electric arc furnace;
[0050] T1-T2 stage: a stage in which the metal material melts in
the electric arc furnace into molten steel, completes oxidative
dephosphorization, and flows into the sealed tapping chute;
[0051] T2-T3 stage: a stage in which the molten steel is deoxidized
in the sealed tapping chute and flows to the refinement storage
bed;
[0052] T3-T4 stage: a stage in which the molten steel flows in the
higher-position end of the refinement storage bed, undergoes
refinement, and completes desulfurization and alloying; and
[0053] T4-T5 stage: a stage in which the molten steel that has been
refined enters the lower-position end of the refinement storage
bed, and is injected into a crystallizer of the conticaster to form
an ingot blank.
[0054] Optionally, a duration of the T0-T1 stage is controlled
within 5-10 min;
[0055] a duration of the T1-T2 stage is controlled within 20-50
min;
[0056] a duration of the T2-T3 stage is controlled within 5-10
min;
[0057] a duration of the T3-T4 stage is controlled within 20-50
min; and
[0058] a duration of the T4-T5 stage is controlled within 10-60
min.
[0059] Optionally, in the T0-T1 stage:
[0060] the detailed process is: adding the metal material by the
continuously feeding device into the electric arc furnace.
[0061] Optionally, in the T1-T2 stage:
[0062] the detailed process is: the electrodes descending, and
being electrified to melt the metal material, turning on the
furnace-wall coherent oxygen lance to flux or form slag to assist
in the smelting, the furnace door automatically discharging slag,
measuring the temperature and components of the molten steel by
using the temperature measuring and sampling device at a tapping
area of the electric arc furnace, further turning on the tapping
mechanism to tap, and the molten steel flowing into the sealed
tapping chute.
[0063] Optionally, in the T2-T3 stage:
[0064] the detailed process is: the molten steel flowing in the
sealed tapping chute, and according to the temperature and
components of the molten steel at the tapping area of the electric
arc furnace, jetting the carbon powder and the silicon powder as
the reducing-agent powders to the steel flow by using the powder
jetting device.
[0065] Optionally, in the T3-T4 stage:
[0066] the detailed process is: performing argon blowing and
stirring by using the bottom-blowing element; by using the charging
hole, measuring the temperature of the molten steel and adding a
smelting auxiliary material, and according to a particular
condition of the molten steel, performing a different feeding
operation at a next charging hole;
[0067] heating and stirring the molten steel by using the induction
coil and/or the plasma gun, and heating the molten steel and
homogenizing the temperature and components; and
[0068] automatically removing molten slag by using the vacuum slag
cleaner or the slag hole.
[0069] Optionally, in the T4-T5 stage:
[0070] the detailed process is: controlling the molten steel to
reach a predetermined standard of the temperature and components,
and feeding into the crystallizer of the conticaster to form an
ingot blank.
[0071] Optionally, the production method comprises, when the
smelting is started, filling up the electric arc furnace with the
metal material, and after the metal material in the electric arc
furnace has completely melted into the molten steel, opening the
tapping mechanism of the electric arc furnace and maintaining the
opened state;
[0072] the molten steel increasingly flowing into the refinement
storage bed via the sealed tapping chute, performing refinement,
removing in time the molten slag by using the vacuum slag cleaner
or the slag hole to prevent the molten slag from entering the
lower-position end of the refinement storage bed, and when the
tapping linking device of the refinement storage bed is full of the
molten steel, opening the tapping hole and maintaining the opened
state;
[0073] the finished molten steel continuously flowing into the
conticaster via the tapping hole, to obtain a finished steel
billet; and
[0074] subsequently realizing uninterrupted production of an ingot
blank from the molten steel.
[0075] Optionally, the production apparatus and method for electric
arc furnace steelmaking with a fully continuous ultra-short process
are based on a 30-300 t electric arc furnace.
[0076] Optionally, because the electric arc furnace, the refinement
storage bed and the conticaster are arranged from higher to lower,
the height of the factory building is greater than the height of
the factory building of ordinary electric arc furnaces by 5-20
m.
[0077] The advantageous effects of the present disclosure are as
follows:
[0078] a) The production apparatus according to the present
disclosure comprises four operation sites of an electric arc
furnace, a sealed tapping chute, a refinement storage bed and a
conticaster, respectively for melting and primary refining, molten
steel flowing, molten-steel desulfurization and alloying, and
continuous casting; and material flow, energy flow and time stream
in the operation sites are in dynamic equilibrium. The present
disclosure can realize stable production, shorten the tap-to-tap
period of the product, reduce the energy consumption and the
material consumption of the smelting, improve the quality of
products, and prolong the equipment life.
[0079] b) The present disclosure can realize fully continuous
steelmaking. After the smelting is started, a metal material is
continuously added into the electric arc furnace, to complete
melting, dephosphorization and so on; a carbon powder, a silicon
powder and so on are jetted into the sealed tapping chute as
reducing-agent powders; and refining is performed at the
higher-position end of the refinement storage bed, to complete
desulfurization, alloying and so on, and the molten steel that has
been refined is stored and heated at the lower-position end of the
refinement storage bed, and continuously flows into the
conticaster, to form an ingot blank.
[0080] c) The present disclosure can realize that the molten-steel
casting is started within the 120 minutes after the metal material
is started to be continuously added, and the uninterrupted
continuous production is maintained for above 80 hours, which
reduces the loss in the energy and the time in the smelting
process. By using the present disclosure, the output is increased
by above 20% as compared with conventional processes, and the
contents of the harmful elements in the ingot blanks such as [P],
[S], [O], [N] and [H] satisfy the requirements on high-quality
steel products. Regarding one ton of the steel, the
electricity-power consumption is reduced by 50 kWh, and the energy
consumption is reduced by above 20 kgce.
BRIEF DESCRIPTION OF THE DRAWINGS
[0081] FIG. 1 shows a schematic structural diagram of a vertical
cross section of the production apparatus for electric arc furnace
steelmaking with a fully continuous ultra-short process according
to an embodiment of the present disclosure;
[0082] FIG. 2 shows a schematic diagram of a planar structure of
the production apparatus for electric arc furnace steelmaking with
a fully continuous ultra-short process according to an embodiment
of the present disclosure; and
[0083] FIG. 3 shows a flow chart of the smelting of the production
apparatus for electric arc furnace steelmaking with a fully
continuous ultra-short process according to Example 1 of the
present disclosure, and a process of the smelting of a conventional
electric arc furnace steelmaking system for comparison.
[0084] In the drawings: 1--electric arc furnace; 101--continuously
feeding device; 102--furnace door; 103--furnace-wall coherent
oxygen lance; 104--electrodes; 105--tapping mechanism;
106--temperature measuring and sampling device; 2--sealed tapping
chute; 201--chute main body; 202--upper through hole; 203--powder
jetting device; 204--lower through hole; 3--refinement storage bed;
301--bottom-blowing element; 302--charging hole; 303--flue;
304--vacuum slag cleaner; 305--induction coil; 306--plasma gun;
307--tapping linking device; 308--tapping hole; 309--slag hole; and
4--conticaster.
DETAILED DESCRIPTION OF THE EMBODIMENTS
[0085] The particular embodiments of the present disclosure will be
described in detail below with reference to the drawings. It should
be noted that the technical features or the combination of the
technical features described in the following embodiments should
not be considered as self-existing, and they may be combined to
achieve better technical effects. In the drawings of the following
embodiments, the same reference numbers in the drawings represent
the same elements or components, and can be applied to different
embodiments.
[0086] As shown in FIGS. 1-3, a production apparatus for electric
arc furnace steelmaking with a fully continuous ultra-short process
comprises an electric arc furnace 1, a sealed tapping chute 2, a
refinement storage bed 3 and a conticaster 4. The electric arc
furnace 1, the refinement storage bed 3 and the conticaster 4 are
arranged from higher to lower, an electric arc furnace 1 tapping
hole located at a higher position is connected to a higher-position
end of the refinement storage bed 3 located at a lower position via
the sealed tapping chute 2, and the conticaster 4 is located below
the lower-position end of the refinement storage bed 3, and is
connected via the tapping hole 308. The sizes of the electric arc
furnace 1, the sealed tapping chute 2, the refinement storage bed 3
and the conticaster 4 are matched.
[0087] The electric arc furnace 1 comprises a continuously feeding
device 101, a furnace door 102, a furnace-wall coherent oxygen
lance 103, electrodes 104, a tapping mechanism 105 and a
temperature measuring and sampling device 106. The continuously
feeding device 101 is a shaft or horizontal continuously feeding
device. The furnace door 102 is located at a furnace wall of the
electric arc furnace, and is able to discharge slag in the smelting
process. The furnace-wall coherent oxygen lance 102 is installed at
a suitable position of the side wall of the electric arc furnace,
and functions to flux the metal material, blow, form slag and so
on. The electrodes 103 are inserted into the electric arc furnace
via a top end of the electric arc furnace. The tapping mechanism
105 employs the principle of siphon, and is able to realize
slag-free tapping. The temperature measuring and sampling device
106 is located over the tapping hole of the tapping mechanism, and
is able to monitor in real time the temperature and components of
tapped molten steel.
[0088] The sealed tapping chute 2 is of a sealed structure, and
comprises a chute main body 201, an upper through hole 202, a
powder jetting device 203 and a lower through hole 204. The chute
main body 201 is constructed by using a refractory material. The
upper through hole 202 is the molten-steel flow-in end, and is
connected to the tapping hole of the electric arc furnace 1. The
powder jetting device 203 is inserted into the chute main body, and
jets a carbon powder, a silicon powder and so on as reducing-agent
powders to the steel flow. The lower through hole 204 is the
molten-steel flow-out end, and is connected to the refinement
storage bed 3, and the lower through hole 204 protrudes below the
liquid level of the molten steel in the refinement storage bed.
[0089] The refinement storage bed 3 is of a sealed structure, and
comprises a bottom-blowing element 301, a charging hole 302, a flue
303, a vacuum slag cleaner 304, an induction coil 305, a plasma gun
306, a tapping linking device 307, a tapping hole 308 and a slag
hole 309. The refinement storage bed 3 is constructed by using a
refractory material, is arranged in the form of a vertical step,
and has one end connected to the sealed tapping chute 2 as the
higher-position end, and has one end connected to the conticaster 4
as the lower-position end. The bottom-blowing element 301 is at a
bottom of the refinement storage bed. The charging hole 302 is
arranged at the top of the refinement storage bed. Optionally, the
temperature measuring and sampling device or a charging tube
protrudes into the refinement storage bed via the charging hole
302. The flue 303 is located at the top of the refinement storage
bed. The vacuum slag cleaner 304 is located behind the last one
charging hole at one end adjacent to the conticaster of the top of
the refinement storage bed, and contacts the slag surface. The
induction coil 305 and/or the plasma gun 306 are arranged at the
bed wall of the refinement storage bed. The tapping linking device
307 is located at the lower-position end of the refinement storage
bed, is able to store an amount of molten steel, and has a
cushioning effect. A slag dam is provided at the connection between
the tapping linking device 307 and the higher-position end of the
refinement storage bed 3, and is able to realize slag-free tapping.
The tapping hole 308 is located at one end of the bottom of the
refinement storage bed that is adjacent to the conticaster, and is
connected to the conticaster 4. The slag hole 309 is an opening at
the furnace wall of the refinement storage bed.
[0090] The method comprises, in a smelting process, adding a metal
material by the continuously feeding device 101 into the electric
arc furnace 1, and melting and primarily refining to become molten
steel; the molten steel entering and flowing in the sealed tapping
chute 2; the molten steel flowing into the refinement storage bed
3, and undergoing molten-steel desulfurization and alloying, to
reach qualified temperature and components; and the molten steel
that has been refined flowing into the conticaster 4, and
undergoing continuous casting, to finally obtain a qualified ingot
blank.
[0091] Optionally, the production method comprises, in the smelting
process, in the electric arc furnace 1, by blowing oxygen and
supplying electricity by using the furnace-wall coherent oxygen
lance 103 and the electrodes 104, melting the metal material and
heating, and in the refinement storage bed 3, and heating the
molten steel by using the induction coil 305 and/or the plasma gun
306.
EXAMPLE 1
[0092] In this Example, the method according to the present
disclosure is applied to a 150 t production apparatus for electric
arc furnace steelmaking with a fully continuous ultra-short process
according to the present disclosure for smelting production. The
sizes of the devices are:
[0093] The capacity of the electric arc furnace is 150 t. The
sealed tapping chute is a circular tube having a length of 3 m and
an inner diameter of 0.3 m. The internal space of the
higher-position end of the refinement storage bed has a length of 4
m, a width of 1 m and a height of 2 m, and the internal space of
the lower-position end of the refinement storage bed has a length
of 1 m, a width of 1 m and a height of 2.5 m. The height difference
between the higher-position end and the lower-position end of the
refinement storage bed is 0.5 m. The conticaster is a 2-machine
6-flow 200.times.200 mm billet caster.
[0094] the detailed process is:
[0095] (1) 0-5 min: a stage in which the metal material is
continuously added into the electric arc furnace;
[0096] wherein the detailed process is: adding the metal material
into the electric arc furnace by using the horizontal continuously
feeding device;
[0097] (2) 5-40 min: a stage in which the metal material melts in
the electric arc furnace into molten steel, completes oxidative
dephosphorization, and flows into the sealed tapping chute;
[0098] wherein the detailed process is: the electrodes descending,
and being electrified to melt the metal material, turning on the
furnace-wall coherent oxygen lance to flux or form slag to assist
in the smelting, the furnace door automatically discharging slag,
measuring the temperature and components of the molten steel by
using the temperature measuring and sampling device at a tapping
area of the electric arc furnace, further turning on the tapping
mechanism to tap, and the molten steel flowing into the sealed
tapping chute; and when the smelting is started, filling up the
electric arc furnace with cold-charge metal material, and after the
metal material in the electric arc furnace has completely melted
into the molten steel, opening the tapping mechanism and
maintaining the opened state;
[0099] (3) 40-50 min: a stage in which the molten steel is
deoxidized in the sealed tapping chute and flows to the refinement
storage bed;
[0100] wherein the detailed process is: the molten steel flowing in
the sealed tapping chute, and according to the temperature and
components of the molten steel at the tapping area of the electric
arc furnace, jetting a carbon powder, a silicon powder and so on as
reducing-agent powders to the steel flow by using the powder
jetting device;
[0101] (4) 50-85 min: a stage in which the molten steel flows in
the higher-position end of the refinement storage bed, undergoes
refinement, and completes desulfurization and alloying;
[0102] wherein the detailed process is: performing argon blowing
and stirring by using the bottom-blowing element; by using the
charging hole, measuring the temperature of the molten steel and
adding a smelting auxiliary material, and according to a particular
condition of the molten steel, performing a different feeding
operation at a next charging hole; heating and stirring the molten
steel by using the induction coil and/or the plasma gun, and
heating the molten steel and homogenizing the temperature and
components; automatically removing molten slag by using the vacuum
slag cleaner or the slag hole; and when the smelting is started,
after the tapping mechanism of the electric arc furnace has been
opened, the molten steel increasingly flowing into the refinement
storage bed via the sealed tapping chute, performing refinement,
removing in time the molten slag by using the vacuum slag cleaner
or the slag hole to prevent the molten slag from entering the
lower-position end of the refinement storage bed, and when the
tapping linking device of the refinement storage bed is full of the
molten steel, opening the tapping hole and maintaining the opened
state; and
[0103] (5) 85-90 min: a stage in which the molten steel that has
been refined enters the lower-position end of the refinement
storage bed, and is injected into a crystallizer of the conticaster
to form an ingot blank;
[0104] wherein the detailed process is: controlling the molten
steel to reach a predetermined standard of the temperature and
components, and feeding into the crystallizer of the conticaster to
form an ingot blank.
[0105] By using the above method, the molten-steel casting is
started at the 90 minutes after the metal material is started to be
continuously added, and the uninterrupted continuous production is
maintained for 100 hours, which reduces the loss in the energy and
the time in the smelting process. The output is increased by 40% as
compared with conventional processes, and the contents of the
harmful elements in the ingot blanks such as [P], [S], [O], [N] and
[H] satisfy the requirements on high-quality steel products.
Regarding one ton of the steel, the electricity-power consumption
is reduced by 50 kWh, and the energy consumption is reduced by 20
kgce.
[0106] Although the present disclosure has provided embodiments of
the present disclosure, a person skilled in the art should
understand that the embodiments of the present disclosure may be
modified without departing from the spirit of the present
disclosure. The above embodiments are merely illustrative, and the
scope of the present disclosure should not be limited to the
embodiments of the present disclosure.
* * * * *