Split maintenance method for Kaldo furnace lining

Abstract

The invention discloses a Kaldo furnace lining split maintenance method which comprises the following steps: S1, after a Kaldo furnace lining reaches a maintenance standard, blowing compressed air into a hearth of a furnace body at a maintenance platform position for natural cooling, and reducing the temperature in the furnace to be within 200 DEG C; s2, fastening bolts at the connecting position of a Kaldo furnace crown and a furnace body are dismantled, the furnace crown is dismantled, the furnace body is divided into two parts, the furnace crown is lifted away, waste furnace linings of the furnace body are dismantled firstly, then the waste furnace linings in the furnace crown are dismantled, and the dismantled furnace linings are packed and stored; s3, annular steel plates are welded to the inner sides of the connecting flanges of the furnace body and the furnace cap, the annular steel plates need to be welded to the upper flange and the lower flange, namely the furnace body and the furnace cap, and full-length welding connection is adopted; s4, a furnace bottom is firstly built according to the size of a hearth, then a furnace body lining is built, and furnace body building is completed within two days; and S5, after the furnace body and the furnace cap are built, anchor flukes are welded to the furnace mouth steel shell, and then ramming materials are used for conducting protective smearing on the furnace mouth.

Description

Technical Field

[0001] The invention relates to the technical field of pyrometallurgical engineering, and in particular to a method for splitting and repairing a Kaldo furnace lining. Background Art

[0002] The Kaldo furnace was originally used for steelmaking, and has now been developed for non-ferrous metal smelting. It can process copper concentrate, scrap copper, lead concentrate, scrap lead, lead dust and copper anode mud. The Kaldo furnace was used to process copper anode mud in 1993. At present, there are about 10 Kaldo furnaces in China for copper anode mud smelting. The Kaldo furnace belongs to the converter molten pool smelting, which has a serious scouring effect on the furnace bricks. Under normal circumstances, the service life of the furnace lining is usually 70-80 days, so the maintenance is more frequent. The maintenance process of the Kaldo furnace usually adopts the integral masonry method, that is, after the service life of the furnace lining expires, the furnace is first stopped to cool down, and then the furnace body is tilted to 0 degrees. The personnel enter the furnace from the slag removal area in front of the furnace through the erected cross bridge to remove the furnace lining. After the lining is removed, the furnace body is tilted to 90 degrees, that is, the furnace mouth is facing the sky to build the furnace lining. The personnel start from the bottom layer to the furnace mouth. After the masonry is completed, the combustion gun is put into the furnace for drying. After the furnace is dried, the material can be put into production. This type of masonry method requires that the masonry workers must be inside the furnace throughout the entire process. Due to the structure of the furnace body, which is smaller at the top and larger at the bottom, the workers are in a confined space during the operation. The gas exchange rate in the space is low, which not only poses risks of suffocation and fumigation, but also the environment is relatively hot and stuffy, and the workers consume a lot of physical energy. At the same time, during the transportation of furnace bricks, workers need to frequently enter and exit the furnace shell for safety reasons, and the outside of the furnace shell is an aerial operation. Therefore, the labor intensity is high and the safety risk is high. This problem is common in various types of Kaldo furnaces and some types of converters.

[0003] Therefore, a method for separate maintenance of Kaldo furnace lining is proposed. Summary of the invention

[0004] In view of the above technical problems, the present invention provides a method for split maintenance of a Kaldo furnace lining.

[0005] In order to achieve the above object, the technical solution of the present invention is as follows: A method for separate maintenance of a Kaldo furnace lining comprises the following steps: S1. After the lining of the Kaldo furnace reaches the maintenance standard, the furnace body is located on the maintenance platform, and compressed air is blown into the furnace for natural cooling to reduce the temperature inside the furnace to below 200°C. After reaching 200°C, an axial flow fan is used to force the furnace to cool down. During this period, the furnace bricks in the furnace are sprayed with water every 2 hours until the temperature inside the furnace drops below 50°C. S2. Disassemble the furnace body, remove the furnace lining, remove the fastening bolts at the connection between the furnace cap and the furnace body of the Kaldo furnace, remove the furnace cap, divide the furnace body into two, lift the furnace cap, first remove the waste lining of the furnace body, and then remove the waste lining in the furnace cap. The removed lining is packed and stored for metal recovery; S3, welding steel plate, welding annular steel plate on the inner side of the connection flange between the furnace body and the furnace cap, the upper and lower flanges, i.e. the furnace body and the furnace cap, must be welded with annular steel plate, the welding method adopts full welding connection, its main function is to squeeze the furnace body lining and support the furnace cap lining, the annular steel plate can be used permanently after one welding; S4, furnace body and furnace cap masonry. According to the size of the furnace, the furnace bottom is first masonry, and then the furnace body and furnace lining are masonry. The furnace body masonry is completed within 2 days. After the furnace body and furnace lining are completed, the furnace cap is installed on the furnace body, and then the furnace cap is masonry. During the masonry process, as the masonry height increases, a special masonry safety frame is set up in the furnace to facilitate personnel maintenance. The furnace cap masonry is completed within 1 day; S5. After the furnace mouth is rammed and the furnace body and furnace cap are built, the anchor claws are welded on the furnace mouth steel shell, and then the furnace mouth is protectively coated with ramming material with a thickness of 40-80mm. After natural drying for 2-3 days, the maintenance is completed.

[0006] Among them, the annular steel plate is welded on the inner side of the connecting flange between the furnace body and the furnace cap. The annular steel plate must be welded on both the furnace body and the furnace cap. The annular steel plate is spliced ​​by 4 pieces of Q235 steel plates with δ=20mm, and the annular steel plate is fully welded.

[0007] Among them, the furnace lining construction process requires first building the furnace body and then building the furnace cap. The furnace lining after the furnace body is built needs to exceed the furnace body flange by 20mm.

[0008] Before installing the furnace cap, refractory mud needs to be applied to the connection between the furnace body and the furnace cap lining. The refractory mud is made of magnesium mud and 10% magnesium chloride aqueous solution with a solid-liquid ratio of 2:1.

[0009] Wherein, the components of the ramming material are magnesia sand: magnesium powder = 2:1.

[0010] The beneficial effects of the present invention are as follows: the present invention can solve the problems of limited space operation, high masonry labor intensity, high safety risk, etc. that are common in the pyrometallurgical extraction process of anode mud smelting and copper pyrometallurgical converter blowing industries. The present invention can stably handle the problems of limited space operation, high masonry labor intensity, high safety risk, etc. in the lining maintenance process of the existing Kaldo furnace maintenance process, and has the effects of simple process, easy operation by personnel, and convenient and fast masonry process. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] The present invention is further described below in conjunction with the accompanying drawings and embodiments: Figure 1 It is a process flow chart of the present invention; DETAILED DESCRIPTION

[0012] In order to make the purpose, technical scheme and advantages of the present invention clearer, the present invention is further described in detail below in conjunction with specific embodiments and with reference to the accompanying drawings. It should be understood that these descriptions are only exemplary and are not intended to limit the scope of the present invention. In addition, in the following description, the description of well-known structures and technologies is omitted to avoid unnecessary confusion of the concept of the present invention.

[0013] Example 1 Implementation of the split overhaul of the Kaldo furnace in a smelter: like Figure 1 As shown in the figure, (1) the lining of the Kaldo furnace reaches the maintenance standard after 89 days of use. The furnace body is hoisted to the maintenance platform and compressed air is blown into the furnace for cooling. After 32 hours, the temperature in the furnace drops to 200°C. Then an axial flow fan is used to cool the furnace. During this period, the furnace bricks in the furnace are sprayed with water every 2 hours to cool them down. After 24 hours, the temperature in the furnace drops to below 50°C.

[0014] (2) Remove the fastening bolts at the connection between the furnace cap and the furnace body of the Kaldo furnace, remove the furnace cap, divide the furnace body into two, lift the furnace cap away, remove 18 tons of waste lining from the furnace body within 24 hours, and remove 5 tons of waste lining from the furnace cap within 8 hours. The removed lining is packed and stored.

[0015] (3) An annular steel plate is welded on the inner side of the flange connecting the furnace body and the furnace cap, and annular steel plates are welded on both the upper and lower flanges. The welding method adopts full welding connection.

[0016] (4) According to the size of the furnace, the furnace bottom is built first, and then the furnace body and lining are built. The furnace body can be built in 40 hours. After the furnace body and lining are built, the furnace cap is installed on the furnace body, and then the furnace cap is built. The furnace cap can be built in 24 hours.

[0017] (5) Anchor claws are welded on the steel shell of the furnace mouth, and then ramming material is used to apply a protective coating to the furnace mouth with a thickness of 50 mm. After natural drying for 2 days, the maintenance is completed.

[0018] After the present invention improves the maintenance method of the Kaldo furnace lining, the maintenance time of the Kaldo furnace lining is shortened by 1.5 days compared with the past. The entire maintenance process does not involve high-risk operations in confined spaces, and effectively solves the problems of stuffy environment during the masonry process, high labor intensity, and low operating efficiency.

[0019] Example 2 Implementation of the split overhaul of the Kaldo furnace in a smelter: like Figure 1As shown in the figure, (1) the lining of the Kaldo furnace reaches the maintenance standard after 95 days of use. The furnace body is hoisted to the maintenance platform and compressed air is blown into the furnace for cooling. After 34 hours, the temperature in the furnace drops to 200°C. Then an axial flow fan is used to cool the furnace. During this period, the furnace bricks in the furnace are sprayed with water every 2 hours to cool them down. After 25 hours, the temperature in the furnace drops to below 50°C.

[0020] (2) Remove the fastening bolts at the connection between the furnace cap and the furnace body of the Kaldo furnace, remove the furnace cap, divide the furnace body into two, lift the furnace cap away, remove 15 tons of waste lining from the furnace body within 24 hours, and remove 4 tons of waste lining from the furnace cap within 8 hours. The removed lining is packed and stored.

[0021] (3) An annular steel plate is welded on the inner side of the flange connecting the furnace body and the furnace cap, and annular steel plates are welded on both the upper and lower flanges. The welding method adopts full welding connection.

[0022] (4) According to the size of the furnace, the furnace bottom is built first, and then the furnace body and lining are built. The furnace body can be built in 40 hours. After the furnace body and lining are built, the furnace cap is installed on the furnace body, and then the furnace cap is built. The furnace cap can be built in 24 hours.

[0023] (5) Anchor claws are welded on the steel shell of the furnace mouth, and then ramming material is used to apply a protective coating to the furnace mouth with a thickness of 50 mm. After natural drying for 2 days, the maintenance is completed.

[0024] After the present invention improves the maintenance method of the Kaldo furnace lining, the maintenance time of the Kaldo furnace lining is shortened by 2 days compared with the past. There is no high-risk operation in confined space in the entire maintenance process, which effectively solves the problems of stuffy environment during the masonry process, high labor intensity of personnel, and low operation efficiency.

[0025] Example 3 Implementation of the split overhaul of the Kaldo furnace in a smelter: like Figure 1 As shown in the figure, (1) the lining of the Kaldo furnace reaches the maintenance standard after 91 days of use. The furnace body is hoisted to the maintenance platform and compressed air is blown into the furnace for cooling. After 33 hours, the temperature in the furnace drops to 200°C. Then an axial flow fan is used to cool the furnace. During this period, the furnace bricks in the furnace are sprayed with water every 2 hours to cool them down. After 23 hours, the temperature in the furnace drops to below 50°C.

[0026] (2) Remove the fastening bolts at the connection between the furnace cap and the furnace body of the Kaldo furnace, remove the furnace cap, divide the furnace body into two, lift the furnace cap away, remove 10 tons of waste lining from the furnace body within 24 hours, and remove 3 tons of waste lining from the furnace cap within 8 hours. The removed lining is packaged and stored.

[0027] (3) An annular steel plate is welded on the inner side of the flange connecting the furnace body and the furnace cap, and annular steel plates are welded on both the upper and lower flanges. The welding method adopts full welding connection.

[0028] (4) According to the size of the furnace, the furnace bottom is built first, and then the furnace body and lining are built. The furnace body is built in 38 hours. After the furnace body and lining are built, the furnace cap is installed on the furnace body, and then the furnace cap is built. The furnace cap is built in 23 hours.

[0029] (5) Weld anchor claws on the steel shell of the furnace mouth, and then use ramming material to apply protective coating to the furnace mouth with a thickness of 50 mm. Let it dry naturally for 2 days, and the maintenance is completed.

[0030] After the present invention improves the maintenance method of the Kaldo furnace lining, the maintenance time of the Kaldo furnace lining is shortened by 2 days compared with the past. There is no high-risk operation in confined space in the entire maintenance process, which effectively solves the problems of stuffy environment during the masonry process, high labor intensity of personnel, and low operation efficiency.

[0031] Example 4 like Figure 1 As shown, a method for splitting and repairing a Kaldo furnace lining comprises the following steps: S1. After the lining of the Kaldo furnace reaches the maintenance standard, the furnace body is located on the maintenance platform, and compressed air is blown into the furnace for natural cooling to reduce the temperature inside the furnace to below 200°C. After reaching 200°C, an axial flow fan is used to force the furnace to cool down. During this period, the furnace bricks in the furnace are sprayed with water every 2 hours until the temperature inside the furnace drops below 50°C. S2. Disassemble the furnace body, remove the furnace lining, remove the fastening bolts at the connection between the furnace cap and the furnace body of the Kaldo furnace, remove the furnace cap, divide the furnace body into two, lift the furnace cap, first remove the waste lining of the furnace body, and then remove the waste lining in the furnace cap. The removed lining is packed and stored for metal recovery; S3, welding steel plate, welding annular steel plate on the inner side of the connection flange between the furnace body and the furnace cap, the upper and lower flanges, i.e. the furnace body and the furnace cap, must be welded with annular steel plate, the welding method adopts full welding connection, its main function is to squeeze the furnace body lining and support the furnace cap lining, the annular steel plate can be used permanently after one welding; S4, furnace body and furnace cap masonry. According to the size of the furnace, the furnace bottom is first masonry, and then the furnace body and furnace lining are masonry. The furnace body masonry is completed within 2 days. After the furnace body and furnace lining are completed, the furnace cap is installed on the furnace body, and then the furnace cap is masonry. During the masonry process, as the masonry height increases, a special masonry safety frame is set up in the furnace to facilitate personnel maintenance. The furnace cap masonry is completed within 1 day; S5. After the furnace mouth is rammed and the furnace body and furnace cap are built, anchor claws are welded on the furnace mouth steel shell, and then the furnace mouth is protectively coated with ramming material with a thickness of 40mm. After natural drying for 2 days, the maintenance is completed.

[0032] Among them, the annular steel plate is welded on the inner side of the connecting flange between the furnace body and the furnace cap. The annular steel plate must be welded on both the furnace body and the furnace cap. The annular steel plate is spliced ​​by 4 pieces of Q235 steel plates with δ=20mm, and the annular steel plate is fully welded.

[0033] Among them, the furnace lining construction process requires first building the furnace body and then building the furnace cap. The furnace lining after the furnace body is built needs to exceed the furnace body flange by 20mm.

[0034] Before installing the furnace cap, refractory mud needs to be applied to the connection between the furnace body and the furnace cap lining. The refractory mud is made of magnesium mud and 10% magnesium chloride aqueous solution with a solid-liquid ratio of 2:1.

[0035] Wherein, the components of the ramming material are magnesia sand: magnesium powder = 2:1.

[0036] Example 5 like Figure 1 As shown, a method for splitting and repairing a Kaldo furnace lining comprises the following steps: S1. After the lining of the Kaldo furnace reaches the maintenance standard, the furnace body is located on the maintenance platform, and compressed air is blown into the furnace for natural cooling to reduce the temperature inside the furnace to below 200°C. After reaching 200°C, an axial flow fan is used to force the furnace to cool down. During this period, the furnace bricks in the furnace are sprayed with water every 2 hours until the temperature inside the furnace drops below 50°C. S2. Disassemble the furnace body, remove the furnace lining, remove the fastening bolts at the connection between the furnace cap and the furnace body of the Kaldo furnace, remove the furnace cap, divide the furnace body into two, lift the furnace cap, first remove the waste lining of the furnace body, and then remove the waste lining in the furnace cap. The removed lining is packed and stored for metal recovery; S3, welding steel plate, welding annular steel plate on the inner side of the connection flange between the furnace body and the furnace cap, the upper and lower flanges, i.e. the furnace body and the furnace cap, must be welded with annular steel plate, the welding method adopts full welding connection, its main function is to squeeze the furnace body lining and support the furnace cap lining, the annular steel plate can be used permanently after one welding; S4, furnace body and furnace cap masonry. According to the size of the furnace, the furnace bottom is first masonry, and then the furnace body and furnace lining are masonry. The furnace body masonry is completed within 2 days. After the furnace body and furnace lining are completed, the furnace cap is installed on the furnace body, and then the furnace cap is masonry. During the masonry process, as the masonry height increases, a special masonry safety frame is set up in the furnace to facilitate personnel maintenance. The furnace cap masonry is completed within 1 day; S5. After the furnace mouth is rammed and the furnace body and furnace cap are built, anchor claws are welded on the furnace mouth steel shell, and then the furnace mouth is protectively coated with ramming material with a thickness of 80mm. After natural drying for 3 days, the maintenance is completed.

[0037] Among them, the annular steel plate is welded on the inner side of the connecting flange between the furnace body and the furnace cap. The annular steel plate must be welded on both the furnace body and the furnace cap. The annular steel plate is spliced ​​by 4 pieces of Q235 steel plates with δ=20mm, and the annular steel plate is fully welded.

[0038] Among them, the furnace lining construction process requires first building the furnace body and then building the furnace cap. The furnace lining after the furnace body is built needs to exceed the furnace body flange by 20mm.

[0039] Before installing the furnace cap, refractory mud needs to be applied to the connection between the furnace body and the furnace cap lining. The refractory mud is made of magnesium mud and 10% magnesium chloride aqueous solution with a solid-liquid ratio of 2:1.

[0040] Wherein, the components of the ramming material are magnesia sand: magnesium powder = 2:1.

[0041] It should be understood that the above specific embodiments of the present invention are only used to illustrate or explain the principles of the present invention, and do not constitute a limitation of the present invention. Therefore, any modifications, equivalent substitutions, improvements, etc. made without departing from the spirit and scope of the present invention should be included in the protection scope of the present invention. In addition, the appended claims of the present invention are intended to cover all changes and modifications that fall within the scope and boundaries of the appended claims, or the equivalent forms of such scope and boundaries.

Claims

1. A method for splitting and repairing a Kaldo furnace lining, characterized in that: The following steps are involved: S1. After the lining of the Kaldo furnace reaches the maintenance standard, the furnace body is located on the maintenance platform, and compressed air is blown into the furnace for natural cooling to reduce the temperature inside the furnace to below 200°C. After reaching 200°C, an axial flow fan is used to force the furnace to cool down. During this period, the furnace bricks in the furnace are sprayed with water every 2 hours until the temperature inside the furnace drops below 50°C. S2. Disassemble the furnace body, remove the furnace lining, remove the fastening bolts at the connection between the furnace cap and the furnace body of the Kaldo furnace, remove the furnace cap, divide the furnace body into two, lift the furnace cap, first remove the waste lining of the furnace body, and then remove the waste lining in the furnace cap. The removed lining is packed and stored for metal recovery; S3, welding steel plate, welding annular steel plate on the inner side of the connection flange between the furnace body and the furnace cap, the upper and lower flanges, i.e. the furnace body and the furnace cap, must be welded with annular steel plate, the welding method adopts full welding connection, its main function is to squeeze the furnace body lining and support the furnace cap lining, the annular steel plate can be used permanently after one welding; S4, furnace body and furnace cap masonry. According to the size of the furnace, the furnace bottom is first masonry, and then the furnace body and furnace lining are masonry. The furnace body masonry is completed within 2 days. After the furnace body and furnace lining are completed, the furnace cap is installed on the furnace body, and then the furnace cap is masonry. During the masonry process, as the masonry height increases, a special masonry safety frame is set up in the furnace to facilitate personnel maintenance. The furnace cap masonry is completed within 1 day; S5. After the furnace mouth is rammed and the furnace body and furnace cap are built, the anchor claws are welded on the furnace mouth steel shell, and then the furnace mouth is protectively coated with ramming material with a thickness of 40-80mm. After natural drying for 2-3 days, the maintenance is completed.

2. A method for separate maintenance of a Kaldo furnace lining according to claim 1, characterized in that: The annular steel plate is welded on the inner side of the connecting flange between the furnace body and the furnace cap. The annular steel plate is welded on both the furnace body and the furnace cap. The annular steel plate is spliced ​​by 4 pieces of Q235 steel plates with a size of δ=20mm. The annular steel plate is fully welded.

3. A method for separate maintenance of a Kaldo furnace lining according to claim 1, characterized in that: The furnace lining construction process requires first building the furnace body and then building the furnace cap. The furnace lining after the furnace body is built needs to exceed the furnace body flange by 20mm.

4. A method for separate maintenance of a Kaldo furnace lining according to claim 1, characterized in that: Before installing the furnace cap, refractory mud needs to be applied at the connection between the furnace body and the furnace cap lining. The refractory mud material is: magnesium mud, 10% magnesium chloride aqueous solution, and the solid-liquid ratio is 2:

1.

5. A method for separate maintenance of a Kaldo furnace lining according to claim 1, characterized in that: The components of the ramming material are magnesia sand: magnesium powder = 2:1.

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