Refractory material repairing method for ignition furnace of sintering machine

Abstract

The invention discloses a sintering machine ignition furnace refractory material repairing method which comprises the following steps: after a castable refractory material at the top of an ignition furnace locally falls off, cleaning the fallen castable refractory material; more than one steel pipe is arranged below the refractory material falling part, and each steel pipe is fixedly connected with more than one anchoring nail; the anchoring nails of each steel pipe are sleeved with multiple layers of fiber blankets, and cooling pipelines are laid on the anchoring nails. The mode that a conventional castable needs to be disassembled and re-poured on a large scale after being shut down for a long time is changed, the high-temperature-resistant fiber blanket is used for repairing, infrared camera monitoring, ignition furnace negative pressure and other programs are used for assisting in controlling interlocking, damaged local refractory materials of the ignition furnace are rapidly repaired, and the sintering production process is safe and smooth after the ignition furnace is repaired and put into operation; user production logistics influences of downstream blast furnaces, steelmaking and the like are small, and huge economic losses are avoided.

Description

Technical Field

[0001] The present invention relates to the metallurgical field, and particularly to a method for repairing refractory materials of an ignition furnace of a sintering machine. Background Art

[0002] The sintering process is an important link in the metallurgical production process.

[0003] As Figure 1 shown, the conventional sintering process flow is as follows: After the ore in the ore bin 1, the limestone in the limestone bin 2, the dolomite in the dolomite bin 3, the coke powder in the coke powder bin 4, the quicklime in the quicklime bin 5, and the return ore in the return ore bin 6 are cut out in the required proportions, they are sent into one or more mixers 8 through the conveyor belt 7 for mixing and granulation, and then added to the mixed material bin 10 through the conveyor belt 9; the mixed material in the mixed material bin 10 is distributed onto the sintering machine 13, ignited by the ignition furnace 11, and after the suction sintering is completed on the sintering machine 13, it enters the annular cooler 14 for air cooling to reduce the temperature; in order to avoid the sudden cooling of the surface sintered ore just ignited by the ignition furnace 11 resulting in poor drum strength, the heat preservation furnace 12 is used for heat preservation.

[0004] Problems existing in the prior art:

[0005] As Figure 1 shown in Fig. 1 and Fig. 2, the top refractory material 11-1 of the ignition furnace 11 and the side wall 11-2 of the ignition furnace are made by casting and curing of castable, and the service life varies from 5 to 10 years. According to the usage situation of the ignition furnace 11, during the annual overhaul period of more than 10 days of shutdown, re-casting treatment is selected. This overhaul mode takes a long time and has a high cost. In actual production, the ignition furnace 11 works at a high temperature of about 1100°C for a long time, and the damage state of the castable refractory material is not completely controlled. Once the refractory material suddenly falls off in a large area, the normal production of sintering cannot be maintained, and there are safety hazards. The sintering machine is forced to suddenly stop for an unplanned long time for re-casting treatment, completely disrupting the logistics organization of downstream units such as blast furnaces and steelmaking, resulting in huge economic losses. Summary of the Invention

[0006] Therefore, the technical problem to be solved by the present invention is to provide a method for repairing refractory materials of an ignition furnace of a sintering machine.

[0007] The technical solution of the present invention is

[0008] A method for repairing refractory materials of an ignition furnace of a sintering machine includes the following steps:

[0009] (1) After the local casting refractory material on the top of the ignition furnace falls off, first clean the fallen casting refractory material;

[0010] (2) Arrange more than 1 steel pipe below the refractory material falling-off part, and fix more than 1 anchor bolt on each steel pipe; a multi-layer fiber blanket is sleeved on the anchor bolt of each steel pipe;

[0011] Slip the first layer of refractory fiber blanket with heat resistance T1 over the first layer of anchor bolts; along the interface between the fallen refractory and the unfallen refractory at the bottom of the first layer of fiber blanket, lay a cooling pipeline in a circle and fix it on the anchor bolts; the water outlet of the water pipe of the cooling pipeline is perpendicular to the advancing direction of the sintering machine; the water inlet pipe of the cooling pipeline passes through the first layer of fiber blanket;

[0012] (3) As described in (2), install the second layer of refractory fiber blanket with heat resistance T2 from top to bottom. The cooling pipeline of the second layer of fiber blanket is arranged at the bottom of the second layer of fiber blanket... the Mth layer of refractory fiber blanket with heat resistance TM. The cooling pipeline of the Mth layer of fiber blanket is arranged at the bottom of the Mth layer of fiber blanket, until the Nth layer of refractory fiber blanket with heat resistance T N is completed; where: T1 ≤ T2 ≤ T3,..., T N (1 ≤ 2 ≤ 3 ≤..... ≤ N); the number of cooling pipelines is M layers, 1 ≤ 2 ≤ 3 ≤..... ≤ M, M < N;

[0013] (4) Detect the flow rate F M冷却水实际 and temperature T M冷却水实际 of the cooling water in the Mth layer respectively; the alarm value set for the cooling water flow rate is F M冷却水设定 , and the alarm value set for the cooling water temperature is T M冷却水设定 (1 ≤ 2 ≤ 3 ≤..... ≤ M..... < N);

[0014] (5) Use an infrared camera to detect the direction away from the sintering machine of the ignition furnace and detect the surface temperature T 红外实际 of the entire first layer of fiber blanket; the alarm temperature set value for the first layer of fiber blanket is T 红外设定 ;

[0015] (6) Install K differential pressure detectors on the side wall of the ignition furnace to detect the pressures in the furnace of the ignition furnace 11 as P1, P2, P3......P K (1 ≤ 2 ≤ 3 ≤..... ≤ K) respectively, and the average pressure P 炉膛实际 in the furnace of the ignition furnace. The expression method is:

[0016]

[0017] (7) When the sintering machine stops due to reasons, the ignition furnace immediately goes out, and the gas combustion for heating up stops; the average pressure P 炉膛实际 in the furnace is controlled to be between -10 and -20 Pa; carry out repairs according to the corresponding faults.

[0018] In step (1), after the refractory castable on the top of the ignition furnace partially falls off, a cavity that penetrates the entire longitudinal section of the furnace body is formed locally in the ignition furnace. First, clean up the fallen refractory castable. The entire cleaning area is in a regular or irregular shape. In step (2), that is, a steel pipe is provided with multiple layers of fiber blankets. The fiber blankets are arranged from top to bottom. The cooling pipelines are arranged at the bottom of each layer of fiber blankets from top to bottom, but not arranged in the last few layers near the bottom. The number of cooling pipelines is M, and the number of fiber blanket layers is N. M and N are natural numbers, and M is less than N.

[0019] According to a method for repairing the refractory of a sintering machine ignition furnace of the present invention, preferably, the connection described in step (2) is welding.

[0020] According to a method for repairing the refractory of a sintering machine ignition furnace of the present invention, preferably, for the fiber blanket sleeved on the anchor bolts in step (2), a nut is put on and welded and fixed to the anchor bolts; the cooling pipeline described in step (2) is in a regular or irregular shape.

[0021] According to a method for repairing the refractory of a sintering machine ignition furnace of the present invention, preferably, for the part of the water pipe outlet after exceeding the sintering machine 13 in step (2), the included angle with the horizontal plane is more than -2 degrees. -2 degrees means below the horizontal plane and the angle is more than 2 degrees.

[0022] According to a method for repairing the refractory of a sintering machine ignition furnace of the present invention, preferably, in step (2), a filler is provided in the gap between the cooling pipeline and the fiber blanket.

[0023] More preferably, the filler is a mixture of fiber blanket powder, refractory mud and glue with a volume ratio of 8 - 10:1 - 2:1. This component and ratio have a better filling effect.

[0024] According to a method for repairing the refractory of a sintering machine ignition furnace of the present invention, preferably, in step (4), a flow meter and a thermometer are configured at the outlet end of each layer of cooling pipeline.

[0025] According to a method for repairing the refractory of a sintering machine ignition furnace of the present invention, preferably, the fiber blanket is a MarforTech blanket. The MarforTech blanket has a microcrystalline structure, can withstand temperatures up to 1600 °C, has low thermal conductivity, resists thermal shock, has low heat storage, and has good heat absorption performance.

[0026] According to a method for repairing the refractory of a sintering machine ignition furnace of the present invention, preferably, the control method for the maintenance in step (7) is:

[0027] ① When the temperature T at a certain place in the infrared detection of the first layer of fiber blanket 红外实际 ≥T 红外设定 the infrared imaging area changes color and shows. When the color change shows in more than 2 consecutive areas, the system automatically alarms to remind the maintenance personnel to arrive at the site and use the filler to fill the color-changing area; ② When When it is [specific condition], it indicates that there are signs of melting damage at the lower part of the fiber blanket of this layer, and it is necessary to cool the cooling pipeline with water; when it is [another specific condition], it indicates that the cooling pipeline configured for the fiber blanket of this layer leaks water, and it is necessary to stop cooling with water.

[0028] In step ①, the infrared imaging area generally shows red under normal conditions.

[0029] Furthermore, the filler in step ① is a mixture of red mud, fiber blanket powder, and glue with a volume ratio of 8 - 10:1 - 2:1.

[0030] Beneficial effects:

[0031] (1) It changes the mode of conventional castables that require large - scale disassembly and re - casting after long - term shutdown.

[0032] (2) Use high - temperature - resistant fiber blankets for repair, and assist in program control interlocks such as infrared camera monitoring and ignition furnace negative pressure, quickly repair the damaged local refractories of the ignition furnace, and ensure the safety and smooth operation of the sintering production process after the repair is put into operation.

[0033] (3) Compared with the conventional large - area disassembly method, this method has local repair with low cost.

[0034] (4) It has little impact on the production logistics of downstream blast furnaces, steelmaking and other users, and avoids huge economic losses. Brief description of the drawings

[0035] Figure 1 is the original process schematic diagram.

[0036] Figure 2a is the side view of the ignition furnace; Figure 2b is the top view of the ignition furnace.

[0037] Figure 3a is the A - A cross - sectional view of the ignition furnace of the present invention; Figure 3b is the top view of the ignition furnace.

[0038] In the figure, 1 - ore bin, 2 - limestone bin, 3 - dolomite bin, 4 - coke powder bin, 5 - quicklime bin, 6 - return ore bin, 7 - conveyor belt, 8 - mixer, 9 - conveyor belt, 10 - mixed material bin, 11 - ignition furnace, 12 - soaking pit, 13 - sintering machine, 14 - annular cooler.

[0039] 11 - 1 ignition furnace refractories, 11 - 2 ignition furnace side wall, 11 - 3 fiber blanket, 11 - 4 cooling pipeline, 11 - 5 infrared camera, 11 - 6 differential pressure detector, 11 - 7 anchor bolt, 11 - 8 steel pipe, 11 - 9 flow rate detection, 11 - 10 temperature detection. Specific implementation manners

[0040] (1) After the refractory material 11-1 on the top of the ignition furnace 11 partially falls off, a cavity running through the entire longitudinal section of the furnace body is formed locally in the ignition furnace. First, clean up the fallen refractory material of the castable. The entire cleaning area is in a regular or irregular shape.

[0041] (2) Weld more than 1 anchor bolt 11-7 on more than 1 steel pipe 11-8. From top to bottom, the first layer of refractory fiber blanket 11-3 with temperature resistance T1 is put on the anchor bolts, and nuts are put on the anchor bolts 11-7 at the bottom of the first layer of fiber blanket and welded and fixed to the anchor bolts 11-7. A cooling pipeline 11-4 with a regular or irregular shape is laid in a circle along the interface between the fallen refractory material and the unfallen refractory material at the bottom of the fiber blanket and fixed on the anchor bolts 11-7. The water pipe outlet is perpendicular to the advancing direction of the sintering machine 13, and the part of the water pipe outlet behind the sintering machine 13 forms an angle of more than -2 degrees with the horizontal plane. The water inlet pipe of the cooling pipeline 11-4 passes through the first layer of fiber blanket, and the gap between the cooling pipeline 11-4 and the fiber blanket is filled with a mixture of fiber blanket powder, refractory mud and glue with a volume ratio of 8:

[0042] 2:1.

[0043] (3) According to the method described in (2), install the second layer of refractory fiber blanket 11-3 with temperature resistance T2, cooling pipeline 11-4... until the installation of the Nth layer of refractory fiber blanket 11-3 with temperature resistance T is completed, where: T1 ≤ T2 ≤ T3... T N (1 ≤ 2 ≤ 3... ≤ N); the number of cooling pipelines is less than the number of fiber blanket layers. N (1 ≤ 2 ≤ 3... ≤ N); the number of cooling pipelines is less than the number of fiber blanket layers.

[0044] (4) A flowmeter 11-9 and a thermometer 11-10 are arranged at the outlet end of each layer of cooling pipeline 11-4 to detect the flow rate F of the cooling water in the Mth layer and the temperature T M冷却水实际 respectively; the alarm value of the cooling water flow rate is set as F M冷却水实际 , and the alarm value of the cooling water temperature is set as T M冷却水设定 (1 ≤ 2 ≤ 3... ≤ M... ≤ N). M冷却水设定 (1 ≤ 2 ≤ 3... ≤ M... ≤ N).

[0045] (5) The infrared camera 11-5 detects the temperature T of the entire surface of the first layer of fiber blanket 11-3 in the direction away from the sintering machine 13 of the ignition furnace 11; the alarm temperature setting value of the first layer of fiber blanket 11-3 is T 红外实际 ; the alarm temperature setting value of the first layer of fiber blanket 11-3 is T 红外设定 .

[0046] (6) Install K differential pressure detectors 11-6 on the side wall of the ignition furnace 11, each detecting the pressures P1, P2, P3... P in the furnace chamber of the ignition furnace 11 K (1 ≤ 2 ≤ 3... ≤ K), and the average value of the pressures in the furnace chamber of the ignition furnace is P 炉膛实际 . The representation method is:

[0047]

[0048] (7) Control program interlock: ① When the sintering machine 13 stops due to faults or other reasons, the ignition furnace 13 immediately goes out, and the gas combustion for temperature rise stops; ② When the sintering machine 13 is running, the furnace pressure P of the ignition furnace 炉膛实际 is controlled at -10 to -20 Pa.

[0049] ③ When the temperature T at a certain place detected by the infrared detection of the first layer of fiber blanket 11-3 红外实际 ≥T 红外设定 , the infrared imaging area at this place changes color and shows (generally shows red). When the color change shows in more than 2 consecutive areas, the system automatically alarms, reminding the maintenance personnel to arrive at the scene and use a mixture of red mud, fiber blanket powder, and glue with a volume ratio of 1:1:2 to fill the color-changing area. ④ A flow meter 11-9 and a thermometer 11-10 are configured at the outlet end of the pipeline 11-4 to detect the flow rate F M冷却水实际 and temperature T M冷却水实际 of the cooling water in the Mth layer respectively; the set alarm value of the cooling water flow rate is F M冷却水设定 , and the set alarm value of the cooling water temperature is T M冷却水设定 . When , it indicates that there is a sign of melting damage under the fiber blanket of this layer, and it is necessary to cool the cooling pipeline 11-4 by passing water; when

[0050] , it indicates that the cooling pipeline 11-4 configured for the fiber blanket of this layer leaks, and it is necessary to stop passing water for cooling.

[0051] Common fiber blankets such as MarforTech blankets have a microcrystalline structure, can withstand temperatures up to 1600 °C, have low thermal conductivity, are resistant to thermal shock,

[0052] have low heat storage, and have good heat absorption performance.

[0053] Using the method of the present invention, after the refractory of the ignition furnace falls off locally, it can be quickly repaired using fiber blankets, etc. It takes 1 to 2 days to quickly start up and resume production. Infrared cameras and other equipment continue to be put into operation after starting up. The production of sintered ore is under control, and downstream users such as blast furnaces and steelmaking can be unaffected.

[0054] Comparative Example 1

[0055] Using the conventional method, after the refractory of the sintering machine ignition furnace falls off, it needs to be largely disassembled and re-cast, which requires about 10 days of shutdown. The sintered ore logistics is suddenly interrupted for a long time. Downstream blast furnace users are forced to significantly reduce production or even shut down, and subsequent users such as steelmaking are affected, resulting in huge economic losses.

Claims

1. A method for repairing refractory materials of an ignition furnace of a sintering machine, characterized in that: It includes the following steps: (1) After the refractory of the castable on the top of the ignition furnace partially falls off, first clean up the fallen refractory of the castable; (2) Arrange more than 1 steel pipe below the refractory falling-off part, and more than 1 anchor bolt is fixedly connected to each steel pipe; multiple layers of fiber blankets are sleeved on the anchor bolts of each steel pipe; The first layer of refractory fiber blanket with temperature T1 is sleeved on the first layer of anchor bolts; a cooling pipeline is laid in a circle along the interface between the fallen refractory and the unfallen refractory at the bottom of the first layer of fiber blanket and fixed on the anchor bolts; the water pipe outlet of the cooling pipeline is perpendicular to the advancing direction of the sintering machine; the water inlet pipe of the cooling pipeline passes through the first layer of fiber blanket; (3) For the method described in (2), install the second layer of heat-resistant fiber blanket with a temperature resistance of T2 from top to bottom. The cooling pipeline of the second layer of fiber blanket is arranged at the bottom of the second layer of fiber blanket... the Mth layer of heat-resistant fiber blanket with a temperature resistance of TM. The cooling pipeline of the Mth layer of fiber blanket is arranged at the bottom of the Mth layer of fiber blanket until the Nth layer of heat-resistant fiber blanket with a temperature resistance of T N is completed; where: T1 ≤ T2 ≤ T3,..., T N (1 ≤ 2 ≤ 3 ≤..... ≤ N); the number of cooling pipelines is M layers, 1 ≤ 2 ≤ 3 ≤..... ≤ M, M < N; (4) Detect the flow rate F of the cooling water in the Mth layer respectively M冷却水实际 and the temperature T M冷却水实际 ; The set alarm value for the cooling water flow rate is F M冷却水设定 , and the set alarm value for the cooling water temperature is T M冷却水设定 (1 ≤ 2 ≤ 3 ≤..... ≤ M..... < N); (5) The infrared camera detects the ignition furnace in the direction away from the sintering machine and detects the surface temperature T of the entire first layer of fiber blanket. 红外实际 The alarm temperature set value for the first layer of fiber blanket is T 红外设定 ; (6) Install K differential pressure detectors on the side wall of the ignition furnace to detect the pressures in the furnace of the ignition furnace as P1, P2, P3... PK K (1 ≤ 2 ≤ 3 ≤... ≤ K), and the average pressure P in the furnace of the ignition furnace 炉膛实际 , and the representation method is When the sintering machine stops due to reasons, the ignition furnace immediately goes out, and the gas combustion for temperature rise stops; the average value P of the furnace pressure 炉膛实际 is controlled between -10 and -20 Pa; maintenance is carried out according to the corresponding faults.

2. The refractory repair method for the ignition furnace of a sintering machine according to claim 1, characterized in that: The connection described in step (2) is welding.

3. A refractory repair method for the ignition furnace of a sintering machine according to claim 1, characterized in that: For the fiber blanket sleeved on the anchor bolt in step (2), a nut is put on and welded and fixed on the anchor bolt; the cooling pipeline described in step (2) is in a regular or irregular shape.

4. A refractory repair method for the ignition furnace of a sintering machine according to claim 1, characterized in that: For the part of the water pipe outlet behind the sintering machine described in step (2) and exceeding, the included angle with the horizontal plane is more than -2 degrees.

5. A refractory repair method for the ignition furnace of a sintering machine according to claim 1, characterized in that: In step (2), there is a filler in the gap between the cooling pipeline and the fiber blanket.

6. A refractory repair method for a sintering machine ignition furnace according to claim 5, characterized in that: Preferably, the filler is a mixture of fiber blanket powder, refractory mud and glue with a volume ratio of 8-10:1-2:

1.

7. A refractory repair method for the ignition furnace of a sintering machine according to claim 1, characterized in that: In step (4), a flow meter and a thermometer are configured at the outlet end of each layer of cooling pipeline.

8. A refractory repair method for the ignition furnace of a sintering machine according to claim 1, characterized in that: The fiber blanket is a Marfordek blanket.

9. A refractory repair method for the ignition furnace of a sintering machine according to claim 1, characterized in that: The control method for the maintenance described in step (7) is: ①The temperature T at a certain location of the first-layer fiber blanket is detected by infrared 红外实际 ≥T 红外设定 When this occurs, the infrared imaging area changes color and displays. When the color change is displayed in more than two consecutive areas, the system automatically alarms, reminding the maintenance personnel to arrive at the scene and use fillers to fill the discolored areas; ②When it indicates that there are signs of melting damage at the lower part of this layer of fiber blanket, and it is necessary to cool the cooling pipeline by passing water; when it indicates that the cooling pipeline configured for this layer of fiber blanket is leaking, and it is necessary to stop cooling by passing water.

10. A refractory repair method for the ignition furnace of a sintering machine according to claim 9, characterized in that: The filler described in step ① is a mixture of red mud, fiber blanket powder and glue with a volume ratio of 8-10:1-2:1.

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