JPS6127489A - By-raw material preheating automatic charging facility on steel manufacture - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Industrial Application Field] This invention is directed to the production of steel, in particular, the production of auxiliary raw materials that are input in the refining stage, which is roughly divided into the oxidation stage and the reduction stage, in an electric furnace. This invention relates to automatic heating equipment for adding heat to auxiliary raw materials during steelmaking, which uses the high heat of air gas to heat the auxiliary raw materials and automatically inputs the required amount of auxiliary raw materials for each period mentioned above.

[Prior art] In general, steel manufacturing, especially cast steel, involves a melting machine in which main raw materials are charged into an electric furnace and melted, and an oxidation stage in which quicklime is added to the molten steel to dephosphorize and oxidize carbon. , further divided into the refining period, which is the reduction period in which quicklime, Fe-3i and Fe-Mn are added to deoxidize and adjust the components.
Conventionally, the auxiliary raw materials used in the refining stage were manually charged at room temperature, or the auxiliary raw materials were heated using a separate heat source and then manually charged, and the high-temperature production gas generated in the electric furnace was released as is. Ta.

[Problems to be Solved by the Invention] Therefore, in the past, the amount of heat necessary to raise the temperature of auxiliary raw materials from room temperature to the melting point temperature was dependent on the arc heat of an electric furnace or a separate heat source. There was a lot of heat loss during operation. Since the high heat of the production gas was not utilized and was released almost as is, efficient use of energy was impossible. When adding auxiliary raw materials at room temperature, it takes a long time for the auxiliary raw materials to melt, so the interfacial reaction time between the molten metal and slag is relatively shortened, and the reactivity in the furnace decreases, causing deterioration of steel quality. There were some negative effects. There were problems such as a decrease in productivity due to manual input of auxiliary materials depending on the experience of the operator, and a large number of defective products with uneven steel quality.

[Purpose of the invention] This invention eliminates these conventional problems and automatically produces the appropriate amount of auxiliary materials at the appropriate time by heating the auxiliary materials using high-temperature gas generated in the furnace. The purpose of the present invention is to provide an automatic heat injection equipment that can save energy, improve productivity, and improve steel quality by adding heat to the furnace, thereby allowing for semi-automation of the refining process.

[Means for Solving the Problems] In order to achieve this object, the present invention has an auxiliary raw material discharge pipe (24) connected to the straight pipe (8) through the pure gas introduction pipe (9), and an auxiliary raw material discharge pipe (24) at the lower stage. Auxiliary raw material storage space (4)
The circulation space (5) for the production gas is communicated with the heat storage chamber (l2) in which the chimney (13) is installed through the production gas exhaust pipe (7), and the secondary gas communication space (5) is communicated with the heat storage chamber (l2) in which the chimney (13) is installed. An auxiliary raw material supply hopper (20) is branched from an auxiliary raw material supply pipe (20) that communicates with the raw material heating chamber (1) and the production gas circulation space (5).
19), and an auxiliary raw material input preparation hopper (27) installed in the lower part of the heat chamber (1) and communicating with the auxiliary raw material input pipe (28).
).

[Example] In the figure, 1 is a heating chamber for auxiliary raw materials, and has an inner wall 2 and an outer wall 3 made of firebrick and iron plate. A large number of ventilation holes 6 are provided to communicate with the gas circulation space 5.

On the upper surface of the heating chamber l for each auxiliary raw material, a true gas introduction pipe 9 is installed in branch communication with the middle of the straight pipe 8 of the electric furnace 7, which is an existing equipment. A beriberi gas steering cone 10 is installed in the production gas circulation space 5 at the lower stage of the introduction hole to adjust the flow of production gas. A discharge pipe 11 for producing air gas is installed in communication with the lower part of the true gas circulation space 5 of each sub-material supply pipe 1, and this discharge pipe 11 passes through a heat storage chamber 12 made of heat storage bricks, etc., and then passes through a chimney. 13 to the atmosphere through an existing dust collector (not shown).

A direction changing damper 15 operated by a synchronous motor 14 is installed at the connection between the existing chimney 8 and the production gas introduction pipe 9. A backflow prevention damper 17 is installed that opens the chimney 13 when the conversion damper 15 starts opening the straight pipe 8 and opening the introduction pipe 9, and closes the chimney 13 when the damper 15 closes the introduction pipe 9. .

A hopper 19 for supplying the auxiliary raw materials transferred by the conveyor 18 to the auxiliary heating chamber 1 is installed at the upper part of the auxiliary raw material heating chamber 1, and the lower opening of the hopper 19 is provided with a An auxiliary raw material supply pipe 20 for selectively supplying auxiliary raw materials to l
are branched and communicated with each other, and a gate 23 operated by a vibration cylinder 22 that vibrates with compressed air supplied from a compression pump 21 is installed in the lower part of each supply pipe 20.

If the installation space of the electric furnace to which this equipment is applied is narrow, the charge can be introduced into the auxiliary raw material heating chamber 1 using a belt conveyor type without a hopper 19.

An auxiliary raw material discharge pipe 24 is installed in the lower stage of each auxiliary raw material heating chamber 1 to communicate with the auxiliary raw material storage space 4 , and the discharge pipe 24 is vibrated by a vibration cylinder 25 .

An auxiliary raw material input preparation hopper 27 is provided at the lower part of the open stage of the auxiliary raw material discharge pipe 24, and the open part of the lower stage of the hopper 27 is communicated with the auxiliary raw material input pipe 28 connected to the electric furnace 7, and the vibrating cylinder 29 A gate 30 is installed which is vibrated by.

A weight measuring device 31 for measuring the weight of the auxiliary raw material to be supplied onto the hopper 27 is installed in the lower part of the auxiliary raw material input preparation hopper 27 .

Each of the dampers and gates includes a thermocouple 32 that measures the temperature of molten steel in the electric furnace 7, a temperature detection device 33 that checks the electromotive force due to the temperature measured by the thermocouple 32, and an electric signal from the temperature detection device 33. Automatically controlled by a control device consisting of a computer device 34 that indicates the unit TLT to drive each damper, gate, etc. at each time based on electric signals from the auxiliary raw material weight measuring device 31, and a control panel 35 that controls the control device. controlled.

An unexplained reference numeral 36 is a control valve such as a solenoid valve for selectively supplying compressed air from the compression pump 24 to each operating part, and 37 is a heat collecting device of the existing equipment.

The present invention is made with the above-described structure, and the functions associated with steelmaking operations will be explained below.

In the early stages of steelmaking, the main raw material is charged into the electric furnace 7 while the damper 15 closes the production gas introduction pipe 9, the existing chimney is opened, and the gate 26 is closed, and the main raw material is supplied with power. dissolve.

That is, during the melting period, there is a lot of dust in the electric gas and the gas is at a low temperature, so existing electric furnace equipment is used.

During or before the melting stage, the conveyor 18 and hopper 19 accommodate the auxiliary raw material in the auxiliary raw material storage space 4 of each heating chamber 1.

At this time, the gates 23 installed in the supply pipes 20 of each auxiliary raw material are selectively opened to supply the corresponding auxiliary raw materials to the heating chamber 1 of each auxiliary raw material.

Next, the control device is set using the control panel 23 under conditions suitable for the refining period.

When melting progresses and the temperature in the electric furnace 7 rises to a temperature corresponding to the refining period, electromotive force due to the temperature measured by the thermocouple 32 is supplied to the temperature detection device 33, and electricity from the temperature detection device 33 is A signal is communicated to computer device 34. When the temperature conditions for each period of the refining period written in the computer device 34 match the electric signal transmitted from the temperature detection device 33, the computer device 34 sends a command to the synchronous motor 14 and uses the conversion damper 15 to remove the existing chimney. While closing 8, the production gas introduction pipe 9 is opened.

At this time, since the motor 16 is interlocked with the synchronous motor 14 when the damper 15 starts opening the beriberi gas introduction pipe 9, the damper 17 opens the chimney 13.

When the beriberi gas introduction pipe 9 is opened, the production gas generated from the electric furnace is introduced into the auxiliary raw material storage space 4 of each auxiliary raw material heating chamber 1 through the introduction pipe 9, and the produced production gas is introduced. heats the auxiliary raw material while passing between the particles of the auxiliary raw material.

Next, the production gas is passed through the ventilation holes 6 drilled in the inner wall 2 of the heat chamber 1.
The production gas flows into the circulation space 5 through the production gas exhaust pipe 11 and is discharged to the heat storage chamber 12.The residual heat is stored by the heat storage bricks inside the heat storage chamber 12, and the remaining heat is stored in the chimney 13 and the dust collector (Fig. (not shown) into the atmosphere.

At this time, the auxiliary raw material is heated from room temperature to 650 to 850°C.

Next, when the temperature in the electric furnace reaches the auxiliary material input temperature for the oxidation period set on the control panel 35, the control device opens the gate 26 of the auxiliary material discharge pipe 24 of the corresponding auxiliary material heating chamber l. It is stacked in the input preparation hopper 27.

The weight of the auxiliary raw materials stacked in the hopper 27 is measured by the measuring device 31, and when the weight approaches the appropriate weight for each period, the gate 26 is vibrated by the vibration cylinder 25 and its opening is further narrowed to close the discharge pipe 24. Closed to prevent overcharging.

Next, when the temperature in the electric furnace reaches a temperature appropriate for charging the auxiliary raw materials at different times, the control device opens the auxiliary raw material input gate 30, and the auxiliary raw materials are charged into the electric furnace 7 through the input pipe 28, and then placed in the hopper. The gate 30, into which the auxiliary materials stored in the gate 27 are completely input, automatically returns and closes.

When the state returns to the melting stage, the chimney 13 is closed by the damper 17, so the hot air stored in the heat storage chamber 12 flows back through the production gas discharge pipe 11 and flows into the heat chamber 9 for each auxiliary material. The heat is transferred to heat the auxiliary raw materials.

Each damper 15.17 and each gate 23.26.30 above
is installed so that manual work can be performed in the event of a malfunction of the control device. In this way, auxiliary raw materials are automatically introduced into the electric furnace at each stage of the refining stage, and when the -th round of steelmaking is completed, the state returns to the melting stage.

As described above, according to this invention, the high-temperature production gas generated from the electric furnace is introduced into the auxiliary raw material heating chamber to heat the auxiliary raw material, thereby significantly reducing the amount of heat required to heat the auxiliary raw material. Since the reaction time between molten steel and slag is extended by introducing the heated auxiliary raw material, the quality of the steel can be improved by improving the reactivity in the furnace.

In addition, since the appropriate amount of auxiliary materials are automatically added at the appropriate time for each period, it is possible to improve steel quality and simplify operations.
This has great effects such as reducing production costs.

[Brief explanation of the drawing]

Fig. 1 is an overall perspective view illustrating one embodiment of the present invention, Fig. 2 is a beriberi gas system diagram of this inventive equipment, Fig. 3 is an auxiliary raw material system diagram of this inventive equipment, and Fig. 4 is It is a schematic diagram of a control device. In the figure, ■ is an auxiliary raw material heating chamber, 4 is an auxiliary raw material storage space,
5 is an exhaust gas circulation space, 6 is a ventilation steel, 8 is a straight pipe, 9 is a beriberi gas introduction pipe, 1o is an exhaust gas steering cone, 11 is a production gas discharge pipe, 12 is a heat storage chamber, 13 is a chimney , 14 is a synchronous motor, 15 is a direction change damper, 16 is a motor, 17 is a backflow prevention damper, 19 is a hopper, 20 is an auxiliary raw material supply pipe,
22, 25, 29 are vibration cylinders, 23, 26, 30 are gates, 24 is an auxiliary raw material discharge pipe, 27 is an auxiliary raw material input preparation hopper, 31 is an auxiliary raw material weight measuring device, 32 is a thermocouple, 33
34 is a temperature detection device, 34 is a computer device, and 35 is a control panel. Agent Patent Attorney Yoshimi Saigo Patent Attorney Yukio Harada Procedural Amendment (October 16, 1985 Michibe Uga, Commissioner of the Patent Office, Patent Application No. 148492 2, 1982, Title of Invention: For steel manufacturing) Automatic heating equipment for auxiliary raw material wire 3, relationship with the case of the person making the amendment Patent applicant address Yong-gyun, Namoogu, Inchineon, South Korea
3-Tong, 351 Name Kim Young-soo Nationality South Korea 4 Agent Address: 105 03-438-22
41 (Representative) Address: 4th floor, Kakuto Building 3, 3-4-17 Toranomon, Minato-ku, Tokyo Name (8005) Patent Attorney Yoshimi Nishio 5 Date of amendment order Voluntary action 7 Contents of amendment (1. Invention (2) As shown in the attached sheet, (3) Figures 5, 6 (a), (b), and (c) are revised to "automatic input equipment for auxiliary raw material wire heat for steelmaking." Addition as follows. Full text amended specification 1, title of the invention automatic wire heat injection equipment for steel making 2, claim 1, an invaginated gas introduction pipe (9) is connected to a continuous straight pipe (8), An auxiliary raw material discharge pipe (24) is installed in the lower stage, and an auxiliary raw material storage space (4) in which a production gas steering cone (10) is installed, and an exhaust gas discharge pipe (11) are connected to an I-type chimney ( 13)
A production gas circulation space (5) connected to a known heat storage chamber (12) in which a heat storage chamber (12) is installed is connected to a storage space r&1 (4) by installing an auxiliary raw material input pipe (1) that communicates with it through a ventilation hole (6). The connected auxiliary raw material supply pipe (20) is branched to the auxiliary raw material supply hopper (19), and the auxiliary raw material feed pipe (28) installed at the bottom of the heating chamber (1) is connected to the auxiliary raw material input pipe (28). A raw material input preparation hopper (27) is installed, and gates (26) are installed at the discharge stage of the waste gas (24) and the input preparation hopper (27).
(30) is installed to automatically feed the auxiliary raw material wire heat. ↓、Gate (26) installed in the auxiliary raw material discharge pipe (24)
The opening and closing are controlled at each stage depending on the temperature in the furnace.1 A game (3) installed at the bottom of the auxiliary material input preparation hopper (27)
0) is controlled to open and close at each time according to the measured value of the auxiliary raw material weight measuring device (31). ↓, The automatic control device is a thermoelectric device that measures the temperature of molten steel in the electric furnace (7)! A temperature detection device (33) that checks the electromotive force due to the temperature measured at ltF (32) and thermoelectricity (32) points, and an auxiliary raw material weight measurement device (31) generates an opening/closing signal for each gate based on the measured values of 1. Computer (34
)if A dynamic input facility that wholesales these items. 3. Detailed Description of the Invention [Field of Industrial Application] This invention utilizes waste gas generated in an electric furnace as an auxiliary material to be input into the refining stage, which is roughly divided into an oxidation stage and a reduction stage, during steel manufacturing, particularly casting steel. This invention relates to automatic heating equipment for adding heat to auxiliary raw materials for steelmaking, which uses the high heat of gas to heat the gas and automatically inputs the required amount of auxiliary raw materials for each period mentioned above. [Prior art] In general, steelmaking, especially cast steel, involves a melting machine in which the main raw materials are charged into an electric furnace and melted, and an oxidation stage in which quicklime is added to the molten steel to dephosphorize and oxidize carbon. , further divided into the refining period, which is the reduction period in which quicklime, Fe-3i and Fe-Mn are added to deoxidize and adjust the components.
Conventionally, the auxiliary raw materials used in the refining stage were manually charged at room temperature, or the auxiliary raw materials were heated using a separate heat source and then manually charged, and the high-temperature waste gas generated in the electric furnace was released as is. Ta. [Problem to be solved by the invention] Therefore, in the past, the amount of heat necessary to raise the temperature of auxiliary raw materials from room temperature to the melting point temperature was dependent on the arc heat of an electric furnace or a separate heat source. There was a lot of heat loss during operation. The high heat of the waste gas was not utilized and was released almost as is, making it impossible to use energy efficiently. When adding auxiliary raw materials at room temperature, it takes a long time for the auxiliary raw materials to be melted, so the interfacial reaction time between the molten metal and slag is relatively shortened, and the reactivity in the furnace decreases, causing deterioration of steel quality. There were some negative effects. There were problems such as a decrease in productivity due to manual input of auxiliary materials depending on the experience of the operator, and a large number of defective products with uneven steel quality. [Purpose of the invention] This invention eliminates these conventional problems and automatically produces the appropriate amount of auxiliary materials at the appropriate time by heating the auxiliary materials using high-temperature waste gas generated in the furnace. The purpose of the present invention is to provide an automatic wire heat input equipment that can save energy, improve productivity, and improve steel quality by inputting steel into the steel, thereby allowing for semi-automation of the refining process. [Means for solving the problem] In order to achieve this object, the present invention includes a waste gas inlet pipe (9) that is connected to the straight pipe (8), and an auxiliary raw material discharge pipe (24) at the lower stage. A well-known heat storage chamber (4) with an auxiliary material storage space (4) in which a waste gas steering cone (10) is installed and a chimney (13) installed through a waste gas discharge pipe (11). An auxiliary raw material heating chamber (1) is installed in which an exhaust gas circulation space (5) communicated with the exhaust gas circulation space (5) communicated with the auxiliary raw material supply pipe (12) is communicated with the storage space (4) through a vent hole (6).
20) is installed as a branch, and an auxiliary raw material supply hopper (19) and an auxiliary raw material input preparation hopper (27) installed at the bottom of the wire heating chamber (1) and communicated with the auxiliary raw material input pipe (28) are installed. A direction changing damper (15) is installed at the communication part between the exhaust gas inlet pipe (9) and the straight pipe (8), a backflow prevention damper (17) is installed at each of the chimney (13), and the exhaust pipe ( 24) and the discharge stage of the input preparation hopper (27), there are gates (2
6) (30) is installed and an auxiliary raw material weight measuring device (31) is installed at the bottom of the input preparation hopper (27). [Example] In the figure, 1 is a wire heating chamber for auxiliary raw materials, and the inner wall 2 and outer wall 3 are made of refractory bricks and iron plates.
The inner wall 2 has a storage space 4 for auxiliary raw materials and a circulation space 5 for waste gas.
A large number of ventilation holes 6 are provided to communicate with each other. On the upper surface of the wire heating chamber 1 for each auxiliary raw material, a waste gas introduction pipe 9 is installed in branch communication, which is connected to the middle of the straight pipe 8 of the electric furnace 7, which is an existing equipment. An exhaust gas control cone 10 for regulating the flow of exhaust gas is installed in the auxiliary raw material storage space 4 below the introduction hole. A waste gas discharge pipe 11 is installed in communication with the lower part of the waste gas circulation space 5 of each auxiliary raw material heating chamber l.
1 is made of heat storage bricks, etc., and passes through a heat storage chamber 12, passes through a chimney 13, and an existing dust collector (not shown), and is opened to the atmosphere. A conversion damper 15 operated by a synchronous motor 14 is installed at the connection between the existing straight pipe 8 and the exhaust gas introduction pipe 9, and a motor 16 electrically connected to the synchronous motor 14 is installed in the chimney 13. Accordingly, when the conversion damper 15 starts closing the straight pipe 8 and opening the waste gas introduction pipe 9, the chimney 13
A damper 17 for preventing backflow is installed so that the chimney 13 can be closed when the exhaust gas introduction pipe 9 is opened and the conversion damper 15 closes the exhaust gas introduction pipe 9. A supply hopper 1 is installed above the auxiliary raw material heating chamber 1 to supply the auxiliary raw material transferred by the conveyor 18 to the wire heating chamber 1.
9 is installed in the lower opening of the supply hopper 19.
Known auxiliary raw material supply pipes 20 are branched and communicated so as to selectively supply auxiliary raw materials to each wire heating chamber 1, and each supply pipe 2
0 is a gate 2 operated by a vibration cylinder 22 that vibrates with compressed air supplied from a compression pump 21.
3 is installed inside. An auxiliary raw material discharge pipe 24 is installed in the lower stage of each auxiliary raw material heating chamber 1 to communicate with the auxiliary raw material storage space 4, and a gate 26 vibrated by a vibration cylinder 25 is installed in each of the discharge pipes 24. An auxiliary material input preparation hopper 27 is installed at the lower part of the open stage of the auxiliary raw material discharge pipe 24, and the lower open part of the input preparation hopper 27 communicates with the auxiliary raw material input pipe '28 connected to the electric furnace 7. Yes, gate 3 opened and closed by vibration cylinder 29
0 is installed. A weight measuring device 31 for measuring the weight of the auxiliary raw material supplied onto the input preparation hopper 27 is installed in the lower part of the auxiliary raw material input preparation hopper 27 . The conversion damper 15, the backflow prevention damper 17, and the gate 23 are manually operated by the operator, and the gate 26.
30 is an electric signal from a thermoelectric band 32 that measures the temperature of molten steel in the electric furnace 7, a temperature detection device 33 that checks the electromotive force due to the temperature measured by the thermoelectric band 32, and an electric signal from the auxiliary raw material weight measuring device 31. Each gate 26.30 according to each period
These devices can be automatically controlled by a control device consisting of a computer 34 that instructs the devices to be driven, and a control panel 35 that controls these devices. As shown in FIG.
It is opened and closed by a signal based on the weight measured in step 1. That is, a signal based on the temperature measured by the thermoelectric band 32 is converted into a digital signal by an A/D converter, and is input to the CPU through the I10 board of the computer 34. When the signal matches the installed temperature, the signal is output from the CPU. The command signal is converted into an analog signal by the I10 boat through a D/A converter, and then sent to the gate 26.3 through the automatic control panel 35.
0, gate 26 is opened and gate 30 is closed. When the gate 26 is opened, the auxiliary raw material wire-heated in the wire heating chamber 1 is loaded into the input preparation hopper 27 and transferred to the weight measuring device 31.
The weight is measured by the electric signal, which is further converted into a digital signal by an A/D converter, and input to the CPU through the I10 board. When the signal is integrated and reaches the set value, a command signal is sent from the CPU. Convert it to an analog signal through a D/A converter on the I10 boat, and send it to the automatic control panel 3.
5 to gate 26 and gate 30 and gate 2
6 is closed, the gate 30 is opened, the weight measurement of the auxiliary raw material is completed, and the auxiliary raw material is introduced. When the addition of auxiliary materials is completed, the gate 30 is also closed,
Continuing to the next stage, the above operation is repeated in the next stage. Reference numeral 36 in this description is a control valve that is the same as a solenoid valve for selectively supplying compressed air from the compression pump 21 to each operating part, and 37 is a combustion chamber of the existing equipment. The present invention is comprised of the above-described structure, and the construction involved in steelmaking operations will be explained below. After tapping the previous molten steel, simple repairs are carried out, the main raw material, old iron, is charged into the electric furnace, electricity is turned on, and work begins during the melting stage. During this melting stage work, there is a lot of waste gas dust and the temperature is lower than the waste heat from the refining stage, so it is not used for the wire heat of the auxiliary raw materials, and is connected to the waste gas inlet pipe 9 and the backflow prevention damper 17 by the conversion damper 15. The chimney 13 is closed and the straight pipe 8, which is the existing equipment, is closed.
is opened, and the exhaust gas is directly discharged into the atmosphere through the existing dust collector (not shown) (block 51 in FIG. 6(a)). During the melting period and during repairs between taps, the waste gas introduction pipe 9 and the chimney 13 are closed by the conversion damper 15 and the backflow prevention damper 17, and the auxiliary materials are transported by the conveyor 18 with the straight pipe 8 open. Then, a gate 23 installed in a known auxiliary raw material supply pipe 20 connected to the auxiliary raw material supply hopper 19 is selectively and manually opened depending on the type of auxiliary raw material, and each auxiliary raw material indirect heating chamber 1 is opened.
The auxiliary raw materials are filled and stored by type. When the filling of the auxiliary raw material is completed, the gate 23 closes the supply pipe 20 (block 52 in FIG. 6(a)). In order to use the high-temperature waste gas generated during the refining period after the melting period of the main raw material is finished and burn-through to heat the auxiliary raw material, the synchronous motor 14 and motor 16 are operated, and the conversion damper 15 and the damper for preventing reverse rotation are activated. At step 17, the existing straight pipe 8 is closed, the exhaust gas introduction pipe 9 and the chimney 13 after the heat storage chamber 12 are opened, and the high-temperature exhaust gas is guided to be sucked into the secondary heating chamber 1, and the induced high heat is The exhaust gas is handled by a circular exhaust gas control cone 1.
Adjustment is made so that the auxiliary raw material flows in a uniformly distributed manner within the indirect heating chamber 1 by setting 0. The high-temperature waste gas guided into the secondary raw material indirect heat chamber 1 passes through 1 ffl between the secondary raw material particles, passes through the ventilation hole 6, and passes through the exhaust gas circulation space 5, during which waste heat is recovered. Heat is guided to the heat storage chamber 12 through the exhaust gas discharge pipe 11 while passing through the exhaust gas circulation space 5. Various auxiliary raw materials filled and housed in the auxiliary raw material indirect heating chamber 1 are collected by 60% by using two methods of waste heat recovery, including indirect heating using a forced heat exchange method and indirect heating using a brick construction strategy.
Heat at 0 to 800°C (Figure 6 (a) block 52)
. Thereafter, the produced gas is guided to the heat storage chamber 12 through the exhaust gas discharge pipe 11, and the residual heat is stored in the heat storage bricks inside the heat storage chamber 12, and then passes through the chimney 13 and the dust collector (not shown) into the atmosphere. released. When the melting period is over, the amount of input of various auxiliary materials is calculated taking into consideration the amount of main raw materials charged, the chemical composition of the target product and the chemical composition of molten steel at burn-through, and the amount of input of various auxiliary materials is calculated during the refining period, oxidation period and reduction period. and 3 to 4
The process is divided into stages, and for each stage, depending on the temperature of the molten steel, the timing of charging the auxiliary raw material and the type of the auxiliary raw material are set and stored in the program of the computer 34 (block 53 in FIG. 6(a)). The flowchart in Figure 6 (a) and (b) shows three types of auxiliary raw materials (S Ml), (S, M2), and (S M 3 ) in three stages (step l), (step 2), and (step 3). This figure shows an example of a steelmaking operation in which steel is divided into two categories. In blocks 54 and 55 of FIG. 6(a), for example, the stage (step 1) corresponds to the oxidation stage during the refining stage, and the stages (step 2) and (step 3) correspond to the reduction stage.
M1) is quicklime, the auxiliary raw material (8M2) is Fe-3i, and the auxiliary raw material (3M3) is Fe-Mn. The auxiliary raw material input temperature (molten steel temperature) in each of the above steps (Step 1), (Step 2), and (Step 3) is set depending on the operation pattern, and the temperature that corresponds to the oxidation period during steelmaking is usually about 1580°C. , the first stage during the reduction period is approximately 1600℃
, the second stage is 1620° C., so the set temperatures for each stage (STI), (ST2), and (ST3) are calculated and set according to the operation pattern. In addition, since the amount (weight) of auxiliary raw materials input for each stage is also determined by the steelmaking pattern, numerical expressions are avoided here and are expressed using symbols. That is, the input amount of the auxiliary raw material (S Ml) in the stage (step 1) is swl, and the input amount of the auxiliary raw material (S M1) in the stage (step 2) is swl.
The input amounts of s ) and (S M 2 ) are sw and -s, respectively.
The input amounts of the auxiliary raw materials (SMl) and (3M3) in the step (step 3) are expressed as k 5W13 and 5W33 (blocks 54 and 55 in FIG. 6(a)) with w and 2. While the refining stage is in progress, the open raw material is continuously heated, and if the operator selects a corresponding program suitable for the refining stage in the CPU of the computer 34, the temperature is detected by the thermoelectric band 32 according to the molten steel temperature measurement. In the device 33, the detected temperature (MTt) is converted into an electrical signal and transmitted to the computer 34 (block 56 in FIG. 6(b)). When the measured temperature (MTl) reaches the set temperature (STl) at a preset stage (step 1), the computer 34 controls the automatic control panel 3 according to the set program.
5 (block 57 in FIG. 6 (b)). The gate 26 of the auxiliary raw material discharge pipe 24 located in the lower part of the indirect heating chamber 1 containing one type of auxiliary raw material (SMl) is opened according to the order determined in the program of the corresponding step (step l) (Fig. 6). (b) Block 58). The indirectly heated auxiliary raw material (SMI) is loaded into the auxiliary raw material input preparation hopper 27 through the auxiliary raw material discharge pipe 24, and is loaded into the auxiliary raw material input preparation hopper 27, and then transferred to the weight measuring device 3.
1 (block 59 in FIG. 6(b)). The weight (MWl) of the auxiliary raw material is sensed by the computer 34,
When the weight of the auxiliary material approaches a set weight (S W 11 ), the vibrating cylinder 25 of the gate 26 is vibrated to gradually narrow the opening of the gate 26 and the discharge pipe 24 is closed to prevent excessive auxiliary material from being loaded. (Figure 6 (b) Block 60
). When the measurement of the auxiliary raw material (SMr) is completed (SWll-M W
1) A command signal from the computer 34 is transmitted to the vibration cylinder 29 through the automatic control panel 35, the gate 30 is opened, and the auxiliary raw material (SMl) is introduced into the molten steel interface in the electric furnace 7 through the auxiliary raw material input pipe 28. (Block 61 in FIG. 6(b)). When the input of the auxiliary material (S M 1) in the first stage (step 1) is completed, the gate 30 is opened according to the command from the computer 34.
is closed (Figure 6 (b) block 62). When the first stage of auxiliary raw material input is completed and the temperature of the molten steel (MT2) reaches the set temperature (ST2) of the stage (step 2) (Figure 6 (b) block 57), the first stage (step l) described above is completed.
) in two steps (Step 2) in the same order as the auxiliary raw material (S
Ml), (3M2) and (blocks 58, 59.
60.61.62) Also, 3-stage (Step 3) auxiliary raw material (S
Ml) and (SM:l) are input. (blocks 57.58.59.60.61.62). Here, 2 steps (block 63 in FIG. 6(c)) and 3
Since there are two types of auxiliary raw materials in the step (block 64 in FIG. 6 (c)), the auxiliary raw materials (SMl) are first transferred to block 58.5.
At 9.60, the measurement is completed, and after measuring the auxiliary raw materials (S M 2 ) or (SM 3 ) in the same order, they are integrated and the input is completed at BLOCK 61.62. That is, in the second stage (Step 2), the measured and integrated weight (MW2) is charged when it matches the set weight (S W I2 + S W22 ) of the auxiliary material (SMt) and (3M2), and in the third stage ( In step 3), the measured cumulative weight (MW
3) is the set weight (SW) of auxiliary raw material (SMt) and (3M3)
ll + 5W3B). In this way, when the chemical composition of the molten steel required in the refining period reaches the target composition and reaches the tapping temperature, the molten steel is tapped and the operation ends with one operation. It is preferable that the gates 26 and 30 be installed so that they can be manually operated in case the computer 34 and the automatic control panel 35 are malfunctioning. As described above, according to the present invention, the high-temperature production gas generated by the electric furnace is introduced into each sub-material heating chamber to indirectly heat the sub-materials, thereby significantly reducing the amount of heat required to heat the sub-materials. It can be saved and by inputting indirectly heated auxiliary raw materials, itl
The reaction time between fjl and slag is extended, and steel quality can be improved by improving in-furnace reactivity. In addition, by automatically adding the appropriate amount of auxiliary materials to each stage at the appropriate time, it is possible to improve steel quality and simplify operations, resulting in reductions in production costs and great effects. It is. 4. Brief description of the drawings Fig. 1 is an overall perspective view illustrating one embodiment of this invention, Fig. 2 is a production gas system diagram of the equipment of this invention, and Fig. 3 is a sub-section of the equipment of this invention. A raw material system diagram, FIG. 4 is a schematic diagram of the control device, FIG. 5 is a block diagram of the equipment of this invention, and FIGS. 6 (a), (b), and (c) are flow charts explaining the invention in detail. . In the figure, 1 is an auxiliary raw material heating chamber, 4 is an auxiliary raw material storage space,
5 is a production gas circulation space, 6 is a ventilation hole, 8 is a straight pipe, 9 is a production gas introduction pipe, 10 is a waste gas operation cone, 11 is a production gas discharge pipe, 12 is a heat storage chamber, 13 is a chimney , 14 is a synchronous motor, 15 is a conversion damper, 16 is a motor, 17 is a backflow prevention damper, 19 is a supply hopper, 20 is an auxiliary raw material supply pipe, 22, 25, 29 are vibration cylinders, 23, 26, 30
24 is a gate, 24 is an auxiliary raw material discharge pipe, 27 is a auxiliary raw material input preparation hopper, 31 is an auxiliary raw material weight measuring device, 32 is a thermoelectric band, 3
3 is a temperature detection device, 34 is a computer, and 35 is a control panel.

Claims (1)

[Claims] 1. The auxiliary raw material storage space (4) is connected to the straight pipe (8) through the waste gas introduction pipe (9), and the auxiliary raw material discharge pipe (24) is installed at the lower stage. The exhaust gas circulation space (5) is connected to the heat storage chamber (12) in which the chimney (13) is installed through the exhaust pipe (7), and the exhaust gas circulation space (5) is connected to the heat storage chamber (12) in which the chimney (13) is installed.
The auxiliary raw material supply hopper (19) is connected to the auxiliary raw material supply pipe (20), which is connected to the auxiliary raw material heat chamber (1) and the exhaust gas circulation space (5), which are connected to each other. 1) A sub-material input preparation hopper (27) installed at the lower stage and communicating with a sub-material input pipe (28). 2. In paragraph 1, a waste gas steering cone (10) is installed in the auxiliary raw material storage space (4) of the heat chamber (1), and the waste gas introduction pipe (9) is installed. A direction changing damper (15) is installed at the joint of the straight pipe (8) so as to be adjustable by a synchronous motor (14), and the chimney (13)
) is equipped with a backflow prevention damper (17) that is opened and closed by a motor (16) that is interlocked with a synchronous motor (14). 3. In item 1, the lower part of the auxiliary raw material supply pipe (20), the discharge pipe (24), and the discharge stage part of the hopper (27) are opened and closed by vibrating cylinders (22), (25), and (29), respectively. Gates (23), (26), and (30) are installed, and an auxiliary raw material weight measuring device (31) is installed at the bottom of the auxiliary raw material input preparation hopper (27). Yu heat automatic injection equipment. 4. In the first, second, or third terms, the direction change damper (15), the backflow prevention damper (17), and the gate (26) installed on the auxiliary material discharge pipe (24) are connected to the temperature inside the furnace. The opening and closing of the auxiliary raw material preparation hopper (2
7) An automatic control device is installed to control the opening and closing of the gate (29) installed at the lower stage according to the measured value of the auxiliary material weight measuring device (31) at each time. Automatic loading equipment. 5. In item 4, the automatic control device includes a thermocouple (32) that measures the temperature of molten steel in the electric furnace, and a temperature detection device (32) that checks the electromotive force due to the temperature measured by the thermocouple (32).
33), and a computer device (34) that generates opening/closing signals for each damper and gate based on the electric signal from the temperature detection device (33) and the measured value from the auxiliary material weight measuring device (31).
) and a control panel for controlling these.