A sintering raw material steam preheating system

Abstract

The present application relates to a sintering raw material steam preheating system, which belongs to the field of sintering technology, and includes: a softened water supply device; a steam drum, wherein the upper part of the steam drum is provided with a softened water inlet, a steam supply port and a water return port, and the lower part of the steam drum is provided with a water supply port; a steam preheater, which is used to steam preheat the raw materials in the small ore tank; a water-cooled igniter, which is arranged above the sintering machine trolley, and the water-cooled igniter includes a water-cooled box and a burner, the water-cooled box has a first through hole penetrating from the upper surface to the lower surface, and the burner head can be inserted into the first through hole, the side wall of the water-cooled box is provided with a cold water inlet, and the upper part of the water-cooled box is provided with a hot water outlet. The sintering raw material steam preheating system provided by the present application can improve the sintering fuel economy and reduce the sintering cost.

Description

Technical Field

[0001] The present application relates to the technical field of sintering, and in particular to a sintering raw material steam preheating system. Background Art

[0002] Sintering is a basic process in the steel industry, which involves sintering powdered raw materials at high temperatures to form aggregates. Usually, the raw materials in the small ore trough need to be preheated with steam before being fed to the trolley to reduce the energy consumption of sintering. At present, the preheating of sintering raw materials requires steam to be supplied by a third party, which increases the cost of steel smelting. At the same time, during the sintering process, the heat generated by the igniter of the sintering machine is used for sintering, and the rest of the heat is naturally dissipated, resulting in poor fuel economy.

[0003] With respect to the above-mentioned related technologies, the inventors believe that the sintering process has the defect of high cost. Summary of the invention

[0004] In order to improve the problem of high cost of sintering process in related technologies, the present application provides a sintering raw material steam preheating system.

[0005] The sintering raw material steam preheating system provided in this application adopts the following technical solution:

[0006] A sintering raw material steam preheating system, comprising:

[0007] A softened water supply device, used for supplying softened water to the steam drum;

[0008] A steam drum, wherein a softened water inlet, a steam supply port and a water return port are arranged at the upper portion of the steam drum, and a water supply port is arranged at the lower portion of the steam drum;

[0009] Steam preheater, used to steam heat the raw materials in the small ore tank;

[0010] A water-cooled igniter is arranged above the sintering machine trolley, and comprises a water-cooled box and a burner. The water-cooled box has a first through hole extending from the upper surface to the lower surface, and the burner head can be inserted into the first through hole. A cold water inlet is arranged on the side wall of the water-cooled box, and a hot water outlet is arranged on the upper part of the water-cooled box.

[0011] The softened water inlet is connected to the softened water supply device through a pipeline; the steam supply port is connected to the steam preheater through a pipeline, and is used to supply steam to the steam preheater; the water supply port is connected to the cold water inlet of the water cooling box through a pipeline, and is used to supply water to the water cooling box; the return water port is connected to the hot water outlet of the water cooling box through a pipeline, and is used to receive return water.

[0012] By adopting the above technical solution, the water-cooled igniter can collect the residual heat of the flame to heat the softened water during the sintering process. After the softened water flows back to the steam drum, steam is generated in the steam drum to preheat the raw materials in the small ore tank.

[0013] Furthermore, a high temperature resistant and corrosion resistant material layer is provided on the lower surface of the water cooling box body, and a heat preservation layer is provided on the upper surface of the water cooling box body.

[0014] By adopting the above technical solution, the high temperature and corrosion resistant material layer can increase the service life of the water cooling box, and the insulation layer can not only keep the water cooling box warm, but also prevent workers from being scalded.

[0015] Furthermore, a manual relief valve and an automatic relief valve are also provided on the upper part of the steam drum. The manual relief valve is used to manually release the steam, and the automatic relief valve is used to automatically release the steam when the steam pressure in the steam drum is greater than or equal to the first limit pressure.

[0016] By adopting the above technical solution, the steam in the steam drum can be released to improve safety.

[0017] Furthermore, the first limiting pressure is 0.8 Mpa.

[0018] Furthermore, the steam drum is provided with a temperature sensor, a pressure sensor and an alarm, wherein the temperature sensor and the pressure sensor are used to detect the temperature and the pressure in the steam drum respectively, and the pressure sensor is connected to the alarm, and when the steam pressure in the steam drum exceeds a second limit pressure, the alarm sends an alarm signal.

[0019] By adopting the above technical solution, when the steam pressure in the steam drum exceeds the second limit pressure, an alarm is triggered, and the staff can promptly investigate and handle the problem to ensure safe operation of the system.

[0020] Furthermore, a self-operated pressure regulating valve is provided between the steam supply port and the steam preheater. When the steam pressure in the steam drum reaches a predetermined pressure, the self-operated pressure regulating valve opens and supplies steam to the steam preheater.

[0021] By adopting the above technical solution, the pressure and temperature of the steam supplied to the steam preheater can meet the raw material preheating requirements.

[0022] Furthermore, the predetermined working pressure is 0.5 MPa.

[0023] Furthermore, the softened water supply device comprises a preparation device, a water storage tank, and a water supply pump which are connected in sequence, and a check valve is provided on the pipeline between the water outlet of the water supply pump and the softened water inlet of the steam drum;

[0024] The steam drum is provided with a liquid level control module. When the liquid level in the steam drum is lower than the minimum limit liquid level, the liquid level control module controls the water supply pump to automatically replenish water into the steam drum.

[0025] By adopting the above technical solution, when the water level in the steam drum is low, the softened water supply device can automatically replenish water into the steam drum to ensure continuous and stable generation of steam.

[0026] Furthermore, the steam preheater includes an annular tube sleeved on the outside of the small ore trough, a steam inlet is provided at one end of the annular tube, the steam inlet is connected to the steam supply port of the steam drum through a pipeline, and a plurality of branch pipes facing the inside of the annular tube are provided on the inner ring surface of the annular tube, the plurality of branch pipes penetrate the side wall of the small ore trough and are inserted into the small ore trough, and the plurality of branch pipes are connected to the annular tube.

[0027] By adopting the above technical solution, the raw materials in the small ore tank can be preheated.

[0028] Furthermore, the sintering raw material steam preheating system also includes: a spare water tank and a spare water pump, wherein the spare water tank and the spare water pump are used to supply water to the steam drum when the softening water supply device fails.

[0029] By adopting the above technical solution, water can be supplied to the steam drum in case of a failure of the softened water supply device, thereby ensuring system safety.

[0030] In summary, the present application includes at least one of the following beneficial technical effects:

[0031] 1. Use water-cooled igniters instead of refractory igniters to collect the residual heat of the flame and generate steam during the sintering process, which improves fuel economy and reduces sintering costs;

[0032] 2. The self-operated pressure regulating valve can ensure the pressure and temperature of the steam entering the steam preheater, thereby ensuring the preheating effect of the raw materials in the small ore tank. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 It is a structural schematic diagram of the sintering raw material steam preheating system;

[0034] Figure 2 It is a structural diagram of the steam preheater.

[0035] Explanation of the reference numerals: 1. Softened water supply device; 11. Preparation equipment; 12. Water storage tank; 13. Water supply pump; 14. Check valve; 2. Steam drum; 21. Softened water inlet; 22. Steam supply port; 23. Water return port; 24. Water supply port; 3. Steam preheater; 31. Annular pipe; 32. Steam inlet; 33. Branch pipe; 4. Water-cooled igniter; 41. Water-cooled box; 411. Cold water inlet; 412. Hot water outlet; 413. First through hole; 414. Insulation layer; 415. Protrusion; 42. Burner; 5. Small ore trough; 6. Trolley; 7. Roller distributor. DETAILED DESCRIPTION

[0036] The following is combined with Figure 1-2 This application is described in further detail.

[0037] Reference Figure 1 The embodiment of the present application discloses a sintering raw material steam preheating system, comprising a softened water supply device 1, a steam drum 2, a steam preheater 3 and a water-cooled igniter 4, wherein the water-cooled igniter 4 comprises a water-cooled box 41 and a burner 42. The softened water supply device 1 supplies softened water to the steam drum 2, and the softened water in the steam drum 2 absorbs heat in the water-cooled box 41 of the water-cooled igniter 4 and then flows back to the steam drum 2 to generate steam, and the steam in the steam drum 2 is transported to the steam preheater 3 to preheat the raw materials in the small ore tank 5.

[0038] Reference Figure 1 The softened water supply device 1 includes a preparation device 11, a water storage tank 12 and a water supply pump 13 which are connected in sequence. The preparation device 11 is a device for preparing softened water based on the sodium ion exchange method. The prepared softened water is stored in the water storage tank 12. When it is necessary to replenish water to the steam drum 2, the softened water is pumped into the steam drum 2 by the water supply pump 13. The number of the water supply pumps 13 can be two in parallel, one of which is a backup. The water outlet of the water supply pump 13 is connected to the softened water inlet 21 of the steam drum 2 through a check valve 14. By setting the check valve 14, the softened water and steam in the steam drum 2 can be prevented from flowing back. The use of softened water can slow down the accumulation of scale in the steam drum 2 and the water-cooled box 41, and extend the service life of the steam drum 2 and the water-cooled igniter 4.

[0039] The steam drum 2 is provided with a liquid level control module, which includes a liquid level detection element and a controller. The liquid level detection element detects the liquid level in the steam drum 2 in real time, and the controller is connected to the liquid level detection element and the upper water pump 13. The liquid level detection element can be a device for detecting the liquid level, such as a float type liquid level gauge, an ultrasonic liquid level gauge, etc., and those skilled in the art can select it according to needs. When the liquid level in the steam drum 2 is lower than the minimum limit liquid level, the liquid level detection element transmits the liquid level signal to the controller, and the controller controls the upper water pump 13 to replenish water in the steam drum 2. When the liquid level in the steam drum 2 reaches the maximum limit liquid level, the controller controls the upper water pump 13 to stop running. For example, the minimum limit liquid level is set to 1 / 3 of the capacity of the steam drum 2, and the maximum limit liquid level is set to 2 / 3 of the capacity of the steam drum 2. When the liquid level in the steam drum 2 is lower than the minimum limit liquid level, the upper water pump 13 automatically runs to replenish water in the steam drum 2; when the liquid level in the steam drum 2 reaches the maximum limit liquid level, the upper water pump 13 automatically stops running. Those skilled in the art may also set the minimum limit liquid level and the maximum limit liquid level as required, which are not specifically limited here.

[0040] Reference Figure 1 The steam drum 2 includes a shell, and a containing space is formed inside the shell. The shell can be made of high temperature and high pressure resistant materials. For example, the shell can be made of boiler steel welded. The upper part of the steam drum 2 is provided with a softened water inlet 21, a steam supply port 22 and a return water port 23, and the lower part of the steam drum 2 is provided with a water supply port 24; the softened water inlet 21 is connected to the softened water supply device 1 through a pipeline; the steam supply port 22 is connected to the steam preheater 3 through a pipeline, and is used to supply steam to the steam preheater 3; the water supply port 24 is connected to the cold water inlet 411 of the water cooling box 41 through a pipeline, and is used to supply water to the water cooling box 41; the return water port 23 is connected to the hot water outlet 412 of the water cooling box 41 through a pipeline, and is used to receive return water. The internal volume of the steam drum 2 is 3m3, the steam volume is 3t / h, and the maximum pressure resistance of the steam drum 2 is 1MPa. The outer surface of the steam drum 2 can be coated with a heat-insulating material, and the heat-insulating layer material can adopt the high temperature resistant heat-insulating material already available in the relevant technology.

[0041] In order to ensure the safety of the steam drum 2, a manual relief valve and an automatic relief valve are also provided on the upper part of the steam drum 2. The manual relief valve is used to manually release the steam in the steam drum 2, and the automatic relief valve is used to automatically release the steam when the steam pressure in the steam drum 2 is greater than or equal to the first limit pressure.

[0042] During the operation of the system, when the steam generation is greater than the steam consumption, the accumulation of steam in the steam drum 2 will cause the pressure in the steam drum 2 to continue to increase. By setting an automatic relief valve, when the steam pressure in the steam drum 2 is greater than or equal to the first limit pressure, automatic relief can be performed to ensure that the pressure in the steam drum 2 is within a safe range. The first limit pressure can be set to 0.8MPa.

[0043] The manual relief valve is a backup for the automatic relief valve. When the automatic relief valve fails and cannot release steam, or when the steam in the steam drum 2 needs to be urgently released under unexpected circumstances, the manual relief valve can be directly opened to release steam.

[0044] A temperature sensor, a pressure sensor and an alarm may be provided on the steam drum 2. The temperature sensor is used to detect the steam temperature in the steam drum 2, the pressure sensor is used to detect the steam pressure in the steam drum 2, the pressure sensor is connected to the alarm, a second limit pressure is provided in the alarm, and when the steam pressure in the steam drum 2 is greater than or equal to the second limit pressure, the alarm sends out an alarm signal. The alarm may be a device capable of sound and light alarm, and the second limit pressure may be set to be greater than or equal to the first limit pressure. For example, when the first limit pressure is 0.8Mpa, the second limit pressure may be set to 0.9Mpa, and when the steam pressure in the steam drum 2 reaches 0.9Mpa, it indicates that the automatic relief valve fails, and the alarm sends out sound and light alarms at this time, and the staff may conduct on-site problem troubleshooting and release steam through the manual relief valve.

[0045] Reference Figure 1 The water-cooled igniter 4 is arranged above the sintering machine trolley 6, and includes a water-cooled box 41 and a burner 42. The water-cooled box 41 is a box structure, and is made of high temperature and high pressure resistant materials. For example, the water-cooled box 41 can be welded from boiler steel. The water-cooled box 41 is arranged above the sintering machine trolley 6, and has a first through hole 413 penetrating from the upper surface to the lower surface. The number of the first through holes 413 is the same as the number of the burners 42. The head of the burner 42 can be inserted into the first through hole 413, and the burner 42 can be fastened to the water-cooled box 41 by bolts or clamping parts. A cold water inlet 411 is arranged on the side wall of the water-cooled box 41, and a hot water outlet 412 is arranged on the upper part of the water-cooled box 41. The cold water inlet 411 is connected to the water supply port 24 of the steam drum 2 through a pipeline, and the hot water outlet 412 is connected to the water return port 23 of the steam drum 2 through a pipeline. The lower edge of the water-cooled box 41 may be provided with a downwardly extending protrusion 415, the lower surface of which is higher than the trolley 6, so as to gather heat. When the blast furnace gas and air are mixed and burned at the head of the burner 42, the flame may be ejected downward from the first through hole 413 to sinter the material on the trolley 6 below the water-cooled igniter 4, and the residual heat of the flame may heat the softened water in the water-cooled box 41.

[0046] In order to improve the life of the water-cooled box 41, a high temperature and corrosion resistant material layer can be provided on the surface of the water-cooled box 41 opposite to the trolley 6, and the high temperature and corrosion resistant material layer can be formed by spraying or brushing with a high temperature and corrosion resistant paint. The upper surface of the water-cooled box 41 can be provided with an insulation layer 414, which can not only improve the heat collection effect of the water-cooled box 41, but also prevent people from being scalded. The insulation layer 414 can be made of aluminum silicate insulation material.

[0047] Reference Figure 2 The steam preheater 3 includes an annular tube 31 arranged outside the small ore trough 5, and a steam inlet 32 ​​is arranged at one end of the annular tube 31, and the steam inlet 32 ​​is connected to the steam supply port 22 of the steam drum 2 through a pipeline. The inner annular surface of the annular tube 31 is provided with a plurality of branch pipes 33 facing the inner side of the annular tube 31, and the plurality of branch pipes 33 penetrate the side wall of the small ore trough 5 and are inserted into the small ore trough 5, and the plurality of branch pipes 33 are connected with the annular tube 31. When the steam enters the annular tube 31 through the pipeline, it can be transported to the inside of the small ore trough 5 through the plurality of branch pipes 33 to preheat the raw materials.

[0048] A self-operated pressure regulating valve may also be provided on the pipeline between the steam supply port 22 of the steam drum 2 and the steam inlet port 32 of the annular pipe 31. The self-operated pressure regulating valve is used to control the pressure of the steam supplied to the small ore tank 5. When the steam pressure in the steam drum 2 reaches a predetermined pressure, the self-operated pressure regulating valve automatically opens and supplies steam to the steam preheater 3 to ensure that the pressure and temperature of the supplied steam are stable. The steam pressure entering the steam preheater 3 can be limited to 0.5 MPa by the self-operated pressure regulating valve. At this time, the steam temperature can reach 150°C, which can heat the raw materials in the small ore tank 5 from 60°C to 90°C.

[0049] During the production process, if the softened water supply device 1 fails to supply water, it will cause water shortage in the steam drum 2 and the water-cooling box 41, and high temperature burning of the water-cooling box 41 will pose a great safety hazard. Therefore, the sintering raw material steam preheating system provided in the present application also includes a spare water tank and a spare water pump. When the softened water supply device 1 fails to supply water, the spare water pump supplies the water in the spare water tank to the steam drum 2 through the softened water inlet 21 of the steam drum 2. Since the spare water tank cannot provide long-term stable water supply, it is not enough to ensure the preheating effect of the raw materials in the small ore tank 5, so the steam can be directly released through the manual release valve on the steam drum 2.

[0050] The working principle of the sintering raw material steam preheating system disclosed in this application is:

[0051] First, before the water-cooled igniter 4 is ignited, softened water is prepared by the softened water supply device 1 and supplied to the steam drum 2. The softened water in the steam drum 2 enters the water-cooled box 41 through the water supply port 24 of the steam drum 2 and the cold water inlet 411 of the water-cooled box 41, and the softened water completely fills the internal space of the water-cooled box 41. When the burner 42 is ignited, the water-cooled box 41 absorbs the residual heat of the flame to heat the softened water in the water-cooled box 41, and the softened water is heated to generate convection and flows into the steam drum 2 through the hot water outlet 412 at the top of the water-cooled box 41 and the return water port 23 on the steam drum 2.

[0052] The heated softened water has a high temperature and its pressure is reduced after entering the steam drum 2, so it is partially vaporized to produce steam. When the steam pressure in the steam drum 2 reaches a predetermined pressure, the self-operated pressure regulating valve automatically opens, and the steam flows out through the steam supply port 22 of the steam drum 2 and is transported to the steam preheater 3 to preheat the raw materials in the small ore tank 5. The temperature of the supplied steam depends on the pressure of the steam. Since the self-operated pressure regulating valve can ensure the stability of the steam pressure, the stability of the steam temperature is also ensured.

[0053] During the operation of the system, when the water level in the steam drum 2 is lower than the minimum limit liquid level, the liquid level control module controls the water supply pump 13 to automatically replenish water into the steam drum 2 to the maximum limit liquid level.

[0054] The raw materials in the small ore trough 5 are preheated by steam and placed in the trolley 6 by the round roller distributor 7 arranged below the small ore trough 5 and sintered under the flame sprayed by the burner 42.

[0055] The sintering raw material steam preheating system disclosed in the present application adopts a water-cooled igniter 4 instead of a refractory igniter to collect the residual heat of the flame and generate steam during the sintering process, which not only improves the economy of the fuel, but also eliminates the need for a third party to supply steam to preheat the raw materials in the small ore tank 5, thereby reducing costs.

[0056] The above are preferred embodiments of the present application, and the protection scope of the present application is not limited thereto. Therefore, any equivalent changes made according to the structure, shape, and principle of the present application should be included in the protection scope of the present application.

Claims

1. A sintering raw material steam preheating system, characterized in that: include: A softened water supply device (1) is used to supply softened water to the steam drum (2); A steam drum (2), wherein the upper portion of the steam drum (2) is provided with a softened water inlet (21), a steam supply port (22) and a water return port (23), and the lower portion of the steam drum (2) is provided with a water supply port (24); A steam preheater (3) for preheating the raw materials in the small ore tank (5) with steam; The water-cooled igniter (4) is arranged above the sintering machine trolley (6). The water-cooled igniter (4) comprises a water-cooled box (41) and a burner (42). The water-cooled box (41) has a first through hole (413) penetrating from the upper surface to the lower surface. The head of the burner (42) can be inserted into the first through hole (413), the side wall of the water-cooled box (41) is provided with a cold water inlet (411), and the upper part of the water-cooled box (41) is provided with a hot water outlet (412); the edge of the lower surface of the water-cooled box (41) can be provided with a protrusion (415) extending downward, and the lower surface height of the protrusion (415) is higher than the trolley (6), which plays a role in gathering heat; when blast furnace gas and air are mixed and burned at the head of the burner (42), the flame can be ejected downward from the first through hole (413) to sinter the material on the trolley (6) located below the water-cooled igniter (4), and the residual heat of the flame can heat the softened water in the water-cooled box (41); The softened water inlet (21) is connected to the softened water supply device (1) through a pipeline; the steam supply port (22) is connected to the steam preheater (3) through a pipeline, and is used to supply steam to the steam preheater (3); the water supply port (24) is connected to the cold water inlet (411) of the water cooling box (41) through a pipeline, and is used to supply water to the water cooling box (41); the return water port (23) is connected to the hot water outlet (412) of the water cooling box (41) through a pipeline, and is used to receive return water; the lower surface of the water cooling box (41) is provided with a high temperature resistant and corrosion resistant material layer, and the upper surface of the water cooling box (41) is provided with a heat insulation layer (414).

2. The sintering raw material steam preheating system according to claim 1, characterized in that: A manual relief valve and an automatic relief valve are also provided on the upper part of the steam drum (2); the manual relief valve is used to manually release the steam in the steam drum (2); and the automatic relief valve is used to automatically release the steam when the steam pressure in the steam drum (2) is greater than or equal to a first limit pressure.

3. The sintering raw material steam preheating system according to claim 2, characterized in that: The first limiting pressure is 0.8 MPa.

4. The sintering raw material steam preheating system according to claim 1, characterized in that: The steam drum (2) is provided with a temperature sensor, a pressure sensor and an alarm. The temperature sensor and the pressure sensor are used to detect the steam temperature and the steam pressure in the steam drum (2) respectively. The pressure sensor is connected to the alarm. When the steam pressure in the steam drum (2) is greater than or equal to a second limit pressure, the alarm sends an alarm signal.

5. The sintering raw material steam preheating system according to claim 1, characterized in that: A self-operated pressure regulating valve is provided between the steam supply port (22) and the steam preheater (3). When the steam pressure in the steam drum (2) reaches a predetermined pressure, the self-operated pressure regulating valve opens and supplies steam to the steam preheater (3).

6. The sintering raw material steam preheating system according to claim 5, characterized in that: The predetermined pressure is 0.5 MPa.

7. The sintering raw material steam preheating system according to claim 1, characterized in that: The softened water supply device (1) comprises a preparation device (11), a water storage tank (12), and a water supply pump (13) which are connected in sequence, and a check valve (14) is provided on the pipeline between the water outlet of the water supply pump (13) and the softened water inlet (21) of the steam drum (2); The steam drum (2) is provided with a liquid level control module. When the liquid level in the steam drum (2) is lower than a minimum limit liquid level, the liquid level control module controls the water supply pump (13) to automatically replenish water into the steam drum (2).

8. The sintering raw material steam preheating system according to claim 1, characterized in that: The steam preheater (3) comprises an annular tube (31) arranged outside the small ore trough (5); a steam inlet (32) is arranged at one end of the annular tube (31); the steam inlet (32) is connected to a steam supply port (22) of a steam drum (2) via a pipeline; a plurality of branch pipes (33) facing the inside of the annular tube (31) are arranged on the inner annular surface of the annular tube (31); the plurality of branch pipes (33) penetrate the side wall of the small ore trough (5) and are inserted into the inside of the small ore trough (5); and the plurality of branch pipes (33) are connected to the annular tube (31).

9. The sintering raw material steam preheating system according to claim 1, characterized in that: Also includes: A standby water tank and a standby water pump are used to supply water to the steam drum (2) when the softened water supply device (1) fails.

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