A long-life and efficient maintenance method for bottom blowing of converter

Abstract

The present invention provides a method for long-life and efficient maintenance of converter bottom blowing. By adjusting the process and combination of converter slag splashing, slag adjustment, slag filling and sand filling during the service life, long-life and efficient maintenance of converter bottom blowing is performed to achieve synchronization of converter bottom blowing furnace age and converter furnace age. The method includes: in 1 to 500 furnaces, slag splashing is started from the first furnace to protect the furnace; in 500 to 1000 furnaces, slag splashing is combined with slag adjustment and slag splashing; in 1000 to 2000 furnaces, slag adjustment and slag splashing are combined with slag filling; in 2000 to 3000 furnaces, slag adjustment and slag splashing are combined with slag filling; in 3000 to 4000 furnaces, slag adjustment and slag splashing, slag filling and sand filling are combined; in 4000 to 5000 furnaces, slag splashing, slag adjustment and slag splashing, sand filling are combined with slag filling without pouring slag. In the furnace of 5000-6000, the slag splashing without pouring slag, the slag splashing with adjustment and sand filling are combined; in the furnace of 6000-7000, the slag splashing without pouring slag, the slag splashing with adjustment and sand filling are combined; in the furnace of 7000-8000, the slag splashing without pouring slag, the slag splashing with adjustment and sand filling are combined; in the furnace of 8000-9000, the slag splashing with adjustment, slag filling and sand filling are combined; in the furnace of 9000-11000, the slag splashing with adjustment and sand filling are combined.

Description

Technical Field

[0001] The present invention relates to the technical field of iron and steel metallurgy, and in particular to a method for long-life and efficient maintenance of bottom blowing of a converter. Background Art

[0002] Compared with the top-blown converter, the bottom-blown gas injection during the combined-blowing converter greatly optimizes the dynamic conditions of the converter molten pool, making the temperature and composition more uniform during the converter smelting process, and further promoting the converter's low iron consumption, low oxidation, high efficiency, and high cleanliness smelting, bringing about a great change in converter smelting. This year, all steel companies have vigorously promoted the application of the combined-blowing converter process.

[0003] With the improvement of the bottom blowing intensity of the converter, higher requirements are put forward for the maintenance of the air-permeable bricks, the base bricks and the furnace bottom. Especially for enterprises smelting low-carbon steel (C<0.05%), the oxidizing property of the slag is higher, and the furnace bottom maintenance is more difficult. The furnace bottom becomes the limiting link of the converter's high efficiency and longevity.

[0004] Especially for enterprises using double converter smelting, the difficulty is even greater. Semi-steel obtained from vanadium-containing molten iron, high-phosphorus molten iron or high-chromium molten iron after vanadium extraction, dephosphorization or dechromization has problems such as low silicon and manganese content, small slag volume, low heat, and relatively serious overoxidation. It is difficult to slag in the converter. If the iron slag forming route is adopted, the TFe content in the slag is high (TFe>18%), which puts higher requirements on the maintenance of the bottom blowing gas supply components in the converter double blowing.

[0005] The conventional maintenance of converters is to use slag splashing, slag patching, sand patching and gunning techniques. The traditional slag patching and asphalt-based patching materials take 40 to 60 minutes to fill the furnace, which cannot meet the needs of efficient and rapid converter smelting. In order to improve the maintenance level of the furnace bottom during the traditional converter slag splashing and patching process, a small bottom blowing flow rate is conventionally used, which cannot meet the needs of efficient and long-lasting combined blowing smelting. Summary of the invention

[0006] According to the technical problems raised above, a method for long-life and efficient maintenance of converter bottom blowing is provided. The present invention mainly achieves the purpose of long-life and efficient maintenance of converter bottom blowing by adjusting the process and combination of converter slag splashing, slag adjustment, slag filling and sand filling during the service life, and realizes synchronization of converter bottom blowing furnace life and converter furnace life.

[0007] The technical means adopted by the present invention are as follows:

[0008] A method for long-life and efficient maintenance of converter bottom blowing is disclosed. The method performs long-life and efficient maintenance of converter bottom blowing by adjusting the processes and combinations of converter slag splashing, slag adjustment, slag supplementation and sand supplementation during the service life of the converter, thereby achieving synchronization of converter bottom blowing furnace life with converter furnace life.

[0009] Furthermore, the process and combined process methods of converter slag splashing, slag adjustment, slag filling and sand filling during the service life are as follows:

[0010] S1, 1 to 500 furnaces, slag splashing and furnace protection starting from the first furnace;

[0011] S2, 500 ~ 1000 furnace, slag splashing and slag adjustment and slag splashing are combined;

[0012] S3, 1000-2000 furnace, slag adjustment, slag splashing and slag filling are combined;

[0013] S4, 2000 ~ 3000 furnace, slag adjustment, slag splashing and slag filling are combined;

[0014] S5, 3000 ~ 4000 furnace, slag adjustment and slag splashing, slag filling and sand filling are combined;

[0015] In S6, 4000-5000 furnace, a combination of non-reversing slag splashing, slag adjustment and slag splashing, and sand filling is carried out;

[0016] In S7, 5000-6000 furnace, a combination of non-reversing slag splashing, slag adjustment and slag splashing, and sand filling is carried out;

[0017] In S8, 6000-7000 furnace, a combination of non-reversing slag splashing, slag adjustment and slag splashing, and sand filling is carried out;

[0018] In the furnace of S9, 7000-8000, a combination of non-reversing slag splashing, slag adjustment and slag splashing, and sand filling is carried out;

[0019] In S10, 8000-9000 furnace, slag adjustment, slag splashing, slag filling and sand filling are combined;

[0020] In the furnaces S11, 9000-11000, slag adjustment, slag splashing and sand filling are combined.

[0021] Furthermore, in the step S1, the slag splashing process is: pouring the slag first and then splashing the slag, and the amount of slag poured is 40% to 60%;

[0022] In step S2, the slag adjustment and slag splashing process is: first pouring slag, then adjusting slag and then splashing slag, the slag pouring amount is 40% to 60%, the slag adjustment slag amount is 2 to 4 kg / ton of steel, and the slag adjustment slag is at least one or two of lime or dolomite; the slag adjustment and slag splashing frequency is 1 to 2 times / shift;

[0023] In the step S3, the slag adjustment and slag splashing process is: first pouring slag, then adjusting slag and then splashing slag, the slag pouring amount is 30% to 50%, the slag adjustment slag amount is 3 to 6 kg / t per ton of steel, and the slag adjustment slag is at least one or two of lime or dolomite; the slag filling process is: without pouring slag, adding one or two of lime or dolomite for slag adjustment and slag filling, the slag adjustment material is at least one or two of lime or dolomite; the amount of slag adjustment material added is 5 to 10 kg / t; the slag filling frequency is 1 time / 48 hours; the slag filling time is 20 to 40 minutes;

[0024] In the step S4, the slag adjustment and slag splashing process is: first pouring slag, then adjusting slag and then splashing slag, the slag pouring amount is 40% to 50%, the slag adjustment slag amount is 3 to 6 kg / t per ton of steel, and the slag adjustment slag is at least one or two of lime or dolomite; the slag filling process is: without pouring slag, adding one or two of lime or dolomite for slag adjustment and slag filling, the slag adjustment material is at least one or two of lime or dolomite; the amount of slag adjustment material added is 5 to 10 kg / t; the slag filling frequency is 1 time / 24 hours; the slag filling time is 20 to 40 minutes;

[0025] In step S5, the sand filling process is as follows: pour out the slag in the furnace and add the filling material to fill the furnace, the filling material is asphalt-based filling material; the amount of filling material added is 5-7 kg / t; the frequency of sand filling is once / 48 hours; the sand filling time is 20-30 minutes;

[0026] In step S6, the slag adjustment and slag splashing process is: after the steel tapping is completed, the slag is adjusted and then splashed, the slag material amount of the slag adjustment is 5-8kg / t of ton steel, the slag material of the slag adjustment is at least one or two of lime or dolomite, the slag splashing without slag pouring is performed 1-2 times per shift, the slag replenishment frequency of the slag splashing without slag pouring is 1 time / 24 hours, and the slag replenishment time is 15 minutes; the remaining furnaces are performed after slag pouring and slag splashing; the sand replenishment frequency is 1 time / 48 hours;

[0027] In step S7, the slag adjustment and slag splashing process is: after the steel tapping is completed, the slag is adjusted and then splashed, the slag material amount of the slag adjustment is 5-8kg / t of steel, the slag material of the slag adjustment is at least one or two of lime or dolomite, and the slag splashing without slag pouring is performed 2-3 times per shift; the slag replenishment frequency of the slag splashing without slag pouring is 1 time / 12 hours, and each slag replenishment lasts 15 minutes; the remaining furnaces perform slag splashing after slag pouring; the sand replenishment frequency is 1 time / 36 hours;

[0028] In step S8, the slag adjustment and slag splashing process is: after the steel tapping is completed, the slag is adjusted and then splashed, the slag material amount of the slag adjustment is 5-8kg / t of steel, the slag material of the slag adjustment is at least one or two of lime or dolomite, and the slag splashing without slag pouring is performed 3-4 times per shift; the slag replenishment frequency of the slag splashing without slag pouring is 1 time / 8 hours, and the slag replenishment time is 15 minutes; the remaining furnaces are performed after slag pouring and slag splashing; the sand replenishment frequency is 1 time / 24 hours;

[0029] In step S9, the slag adjustment and slag splashing process is: after the steel tapping is completed, the slag is adjusted and then splashed, the slag material amount of the slag adjustment is 5-8kg / t of steel, the slag material of the slag adjustment is at least one or two of lime or dolomite, and the slag splashing without slag pouring is performed 4-6 times per shift; the slag replenishment frequency of the slag splashing without slag pouring is 1 time / 6 hours, and each slag replenishment lasts 15 minutes; the remaining furnaces perform slag splashing after slag pouring; the sand replenishment frequency is 1 time / 12 hours;

[0030] In the step S10, the slag filling frequency is once every 12 hours; the sand filling frequency is once every 8 hours;

[0031] In the step S11, the frequency of sand replenishment is once every 4 hours.

[0032] Furthermore, the process of adjusting slag splashing and bottom blowing gas supply is: the bottom blowing flow rate is 70~100Nm 3 / h·branch, bottom blowing time t=T+30s, where T is the top blowing nitrogen splashing time.

[0033] Furthermore, the process of slag filling bottom blowing gas supply is: 0~10min, bottom blowing flow rate is 30~40Nm 3 / h·Branch; 10~20min, bottom blowing flow rate is 40~50Nm 3 / h·Branch; 20~30min, bottom blowing flow rate is 50~70Nm 3 / h·branch.

[0034] Furthermore, the process of sand filling bottom blowing air supply is: 0-10min, bottom blowing flow rate is 20-30Nm 3 / h·Branch; 10~20min, bottom blowing flow rate is 30~40Nm 3 / h·Branch; 20~30min, bottom blowing flow rate is 40~60Nm 3 / h·branch.

[0035] Furthermore, in the step S11, the process of sand filling in the furnace at 9000-11000 once / 4 hours is: slag adjustment and slag splashing-sand filling.

[0036] Compared with the prior art, the present invention has the following advantages:

[0037] 1. The present invention achieves the purpose of long-life and efficient maintenance of converter bottom blowing by adjusting the processes and combinations of converter slag splashing, slag adjustment, slag filling and sand filling during the service life, thereby achieving synchronization between the converter bottom blowing life and the converter life.

[0038] 2. The present invention can shorten the converter refilling time and stabilize the lining thickness of the furnace body by systematically adjusting the maintenance task volume during different periods of the furnace service, thereby ensuring the converter bottom blowing effect and achieving synchronization between the converter bottom blowing life and the converter life.

[0039] Based on the above reasons, the present invention can be widely promoted in the fields of converter smelting and the like. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0041] Figure 1 It is a process flow chart of the present invention. DETAILED DESCRIPTION

[0042] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features in the embodiments can be combined with each other. The present invention will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0043] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. The following description of at least one exemplary embodiment is actually only illustrative and is by no means intended to limit the present invention and its application or use. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0044] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit exemplary embodiments according to the present invention. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprising" and / or "including" are used in this specification, it indicates the presence of features, steps, operations, devices, components and / or combinations thereof.

[0045] Unless otherwise specifically stated, the relative arrangement, numerical expressions and numerical values ​​of the parts and steps described in these embodiments do not limit the scope of the present invention. At the same time, it should be clear that, for ease of description, the sizes of the various parts shown in the drawings are not drawn according to the actual proportional relationship. The technology, methods and equipment known to ordinary technicians in the relevant field may not be discussed in detail, but in appropriate cases, the technology, methods and equipment should be regarded as a part of the authorization specification. In all examples shown and discussed here, any specific value should be interpreted as being merely exemplary, rather than as a limitation. Therefore, other examples of exemplary embodiments may have different values. It should be noted that similar reference numerals and letters represent similar items in the following drawings, so once a certain item is defined in an accompanying drawing, it does not need to be further discussed in subsequent drawings.

[0046] The purpose of the present invention is to achieve long-life and high-efficiency of converter bottom blowing, which is difficult to achieve by using traditional conventional maintenance processes. The present invention provides a long-life and high-efficiency maintenance method for converter bottom blowing, which achieves the purpose of long-life and high-efficiency maintenance of converter bottom blowing by adjusting the processes and combinations of converter slag splashing, slag adjustment, slag filling and sand filling during the service life, and achieves synchronization of converter bottom blowing furnace life and converter furnace life.

[0047] The invention provides a method for long-life and efficient maintenance of converter bottom blowing, which achieves the purpose of long-life and efficient maintenance of converter bottom blowing by adjusting the processes and combinations of converter slag splashing, slag adjustment, slag filling and sand filling during the service life, and realizes synchronization of converter bottom blowing furnace life with converter furnace life.

[0048] As a preferred embodiment, the process and combined process methods of converter slag splashing, slag adjustment, slag filling and sand filling during the service life are:

[0049] In furnaces S1, 1 to 500, slag splashing is started from the first furnace to protect the furnace. The slag splashing process is: pour the slag first and then splash the slag, and the slag pouring amount is 40% to 60%. This method is used at this stage to avoid exposing the furnace bottom, let the slag layer cover the furnace bottom, promote the formation of mushroom heads of the breathable bricks, and lay the foundation for long-term re-blowing.

[0050] In S2, 500-1000 furnaces, slag splashing and slag adjustment and splashing are combined. The slag adjustment and splashing process is: first pouring slag, then slag adjustment and then slag splashing. The slag pouring amount is 40%-60%, the slag adjustment slag amount is 2-4kg / ton of steel, and the slag adjustment slag is at least one or two of lime or dolomite; the slag adjustment and splashing frequency is 1-2 times / shift;

[0051] S3. In the 1000-2000 furnace, slag adjustment, slag splashing and slag filling are combined. The slag adjustment and slag splashing process is: first pour the slag, then adjust the slag and then splash the slag. The slag pouring amount is 30%-50%, the slag material amount for slag adjustment is 3-6kg / t per ton of steel, and the slag material for slag adjustment is at least one or two of lime or dolomite; the slag filling process is: without pouring the slag, add one or two of lime or dolomite for slag adjustment and slag filling, and the slag material for slag adjustment is at least one or two of lime or dolomite; the amount of slag material added is 5-10kg / t; the frequency of slag filling is 1 time / 48 hours; the slag filling time is 20-40min; at this stage, the re-blowing effect of the converter is usually the best, the ventilation smoothness is high, the TFe content of the slag is low, and a certain amount of MgO material is added to improve the furnace protection effect of the slag, and the adjusted slag is used to maintain the furnace bottom and air bricks to slow down the erosion of the mushroom heads of the air bricks.

[0052] S4, 2000 ~ 3000 furnace, slag adjustment and slag splashing are combined with slag filling, the slag adjustment and slag splashing process is: first pour the slag, then adjust the slag and then splash the slag, the slag pouring amount is 40% ~ 50%, the slag material amount of slag adjustment is 3 ~ 6kg / t per ton of steel, and the slag material for slag adjustment is at least one or two of lime or dolomite; the slag filling process is: without pouring slag, add one or two of lime or dolomite for slag adjustment and slag filling, the slag material is at least one or two of lime or dolomite; the amount of slag material added is 5 ~ 10kg / t; the slag filling frequency is 1 time / 24 hours; the slag filling time is 20 ~ 40min; at this stage, the re-blowing effect of the converter is usually better, the ventilation smoothness is high, the TFe content of the slag is low, and the thickness of the furnace bottom is eroded to a certain extent, so the amount of slag retention is increased, and a certain amount of MgO material is added to improve the furnace protection effect of the slag, and the adjusted slag is used to maintain the furnace bottom and air bricks to slow down the erosion of the mushroom head of the air bricks and the furnace bottom.

[0053] In the furnace of S5, 3000-4000, slag adjustment, slag splashing, slag patching and sand patching are combined. The sand patching process is to pour out the slag in the furnace and add the patching material to patch the furnace. The patching material is asphalt-based patching material; the amount of patching material added is 5-7kg / t; the frequency of sand patching is 1 time / 48 hours; the sand patching time is 20-30min; at this stage, the re-blowing effect of the converter is usually weakened to a certain extent, the ventilation fluency is general, the slag TFe content is about 18%, and the thickness of the furnace bottom is eroded to a certain extent. Therefore, sand patching is added on the basis of slag adjustment, slag splashing and slag patching. The principle of slag adjustment, slag splashing and slag patching is to increase the amount of slag left for slag splashing and slag patching, and add a certain amount of MgO material to improve the furnace protection effect of slag, and use the adjusted slag to maintain the furnace bottom and air bricks, and slow down the erosion of the air brick mushroom head and furnace bottom. Sand patching uses asphalt-based patching materials to sinter and bond the furnace lining, increase the thickness of the furnace lining, and control the erosion of the furnace lining by slag with a higher TFe content.

[0054] In the furnace of S6, 4000-5000, slag splashing without pouring slag, slag splashing with slag adjustment and sand filling are combined. The slag splashing process is: slag splashing after steel tapping, slag adjustment and slag splashing, the amount of slag adjustment is 5-8kg / t per ton of steel, and the slag adjustment slag is at least one or two of lime or dolomite. Slag splashing without pouring slag is performed 1-2 times per shift, and the frequency of slag filling without pouring slag splashing is 1 time / 24 hours, and each slag filling lasts 15 minutes; the rest of the furnaces are slag splashing after pouring slag; the frequency of sand filling is 1 time / 48 hours; the FeO content of the slag at this stage is >17%, which has a certain corrosive effect on the refractory of the furnace body, and the slag filling process is no longer used. Use asphalt-based filling materials with better filling effect to sinter and bond the furnace lining, increase the thickness of the furnace lining, control the erosion of the furnace lining by the slag with higher FeO content, and maintain the erosion rate of the furnace bottom within a controllable range.

[0055] In the furnaces of S7, 5000-6000, slag splashing without pouring slag, slag adjustment and slag splashing, and sand filling are combined. The slag adjustment and slag splashing process is: after the steel is tapped, the slag is not poured, and the slag is adjusted and then splashed. The amount of slag adjustment slag is 5-8kg / t per ton of steel. The slag adjustment slag is at least one or two of lime or dolomite. Slag splashing without pouring slag is performed 2-3 times per shift; the frequency of slag filling without pouring slag is 1 time / 12 hours, and each slag filling lasts 15 minutes; the remaining furnaces are slag splashing after pouring slag; the frequency of sand filling is 1 time / 36 hours; the FeO content of the slag at this stage is >18%, which has a certain corrosive effect on the refractory materials of the furnace body, and the slag filling process is no longer used. The frequency of slag splashing without pouring slag is increased, and asphalt-based filling materials with better filling effect are used to sinter and bond the furnace lining, increase the thickness of the furnace lining, control the erosion of the furnace lining by the slag with a higher FeO content, and maintain the erosion rate of the furnace bottom within a controllable range.

[0056] In the furnaces of S8, 6000-7000, a combination of slag splashing without pouring slag, slag adjustment and slag splashing, and sand filling is carried out. The slag adjustment and slag splashing process is: after the steel is tapped, the slag is not poured, and the slag is adjusted and then splashed. The amount of slag adjustment slag is 5-8kg / t per ton of steel. The slag adjustment slag is at least one or two of lime or dolomite. The slag splashing without pouring slag is performed 3-4 times per shift; the frequency of slag filling without pouring slag is 1 time / 8 hours, and each slag filling lasts 15 minutes; the other furnaces are slag splashing after pouring slag; the frequency of sand filling is 1 time / 24 hours; the FeO content of the slag at this stage is >19%, which has a certain corrosive effect on the refractory materials of the furnace body, and the slag filling process is no longer used. The frequency of slag splashing without pouring slag is increased, and asphalt-based filling materials with better filling effect are used to sinter and bond the furnace lining. The frequency of sand filling is increased to increase the thickness of the furnace lining, control the erosion of the furnace lining by the slag with a higher FeO content, and maintain the erosion rate of the furnace bottom within a controllable range.

[0057] In the furnaces of S9, 7000-8000, a combination of slag splashing without pouring slag, slag adjustment and slag splashing, and sand filling is carried out. The slag adjustment and slag splashing process is: after the steel is tapped, the slag is not poured, and the slag is adjusted and then splashed. The amount of slag adjustment slag is 5-8kg / t per ton of steel. The slag adjustment slag is at least one or two of lime or dolomite. The slag splashing without pouring slag is performed 4-6 times per shift; the frequency of slag filling without pouring slag is 1 time / 6 hours, and each slag filling lasts 15 minutes; the other furnaces are slag splashing after pouring slag; the frequency of sand filling is 1 time / 12 hours; the FeO content of the slag at this stage is >20%, which has a certain corrosive effect on the refractory materials of the furnace body, and the slag filling process is no longer used. The frequency of slag splashing without pouring slag is increased, and asphalt-based filling materials with better filling effect are used to sinter and bond the furnace lining. The frequency of sand filling is increased to increase the thickness of the furnace lining, control the erosion of the furnace lining by the slag with a higher FeO content, and maintain the erosion rate of the furnace bottom within a controllable range.

[0058] In the furnaces of S10, 8000-9000, slag adjustment, slag splashing, slag patching and sand patching are combined, with the slag patching frequency of 1 time / 12 hours; the sand patching frequency of 1 time / 8 hours; the FeO content of the slag at this stage is >21%, which has a certain corrosive effect on the refractory materials of the furnace body, and the slag patching process is no longer used. The frequency of slag splashing without pouring slag is increased, and asphalt-based patching materials with better patching effect are used to sinter and bond the furnace lining. The frequency of sand patching is increased to increase the thickness of the furnace lining, control the erosion of the furnace lining by the slag with higher FeO content, maintain the erosion rate of the furnace bottom within a controllable range, ensure that the furnace bottom thickness is >500mm and keep the furnace bottom thickness stable, and create conditions for safe shutdown.

[0059] S11, 9000 ~ 11000 furnace, slag adjustment and splashing are combined with sand filling; the frequency of sand filling is 1 time / 4 hours. At this stage, the FeO content of the slag is >21%, which has a certain erosion effect on the refractory materials of the furnace body, and the slag filling process is no longer used. The frequency of slag splashing without pouring slag is increased, and asphalt-based furnace filling materials with better filling effect are used to sinter and bond the furnace lining. The frequency of sand filling is increased to ensure the thickness of the furnace bottom, control the erosion of the furnace lining by the slag with higher FeO content, ensure that the furnace bottom thickness is >400mm and keep the furnace bottom thickness stable, and achieve safe shutdown.

[0060] As a preferred embodiment, the slag-adjusting and slag-splashing bottom blowing gas supply process is: the bottom blowing flow rate is 70-100Nm 3 / h·Branch, bottom blowing time t=T+30s, T is the top blowing nitrogen slag splashing time. Ensure that the air path of the air-permeable brick is unobstructed after slag splashing and is not blocked.

[0061] As a preferred embodiment, the slag filling bottom blowing gas supply process is: 0-10min, the bottom blowing flow rate is 30-40Nm 3 / h·Branch; 10~20min, bottom blowing flow rate is 40~50Nm 3 / h·Branch; 20~30min, bottom blowing flow rate is 50~70Nm 3 / h·Branch. It promotes the solidification speed of slag on the surface of air-permeable bricks during slag filling so that the air-permeable bricks will not be blocked.

[0062] As a preferred embodiment, the sand filling bottom blowing air supply process is: 0-10min, the bottom blowing flow rate is 20-30Nm 3 / h·Branch; 10~20min, bottom blowing flow rate is 30~40Nm 3 / h·Branch; 20~30min, bottom blowing flow rate is 40~60Nm 3 / h·Branch. It accelerates the solidification speed of slag on the surface of air bricks during sand filling so that the air bricks will not be blocked.

[0063] As a preferred implementation, the process of sand filling in the furnace at 9000-11000 once / 4 hours is: slag adjustment, slag splashing-sand filling. Ensure that the thickness of the furnace bottom is stable and controlled, the surface of the air brick is covered with a slag layer, and the surface of the air brick is always covered with a slag layer during the furnace filling. The thickness of the air brick furnace base is consistent with the thickness of the furnace, so that the position of the air brick will not become the weakest link of the furnace body.

[0064] The present invention is independently developed and implemented.

[0065] A 200-ton steelmaking converter in a steel and vanadium steelmaking plant uses semi-steel smelting after vanadium extraction. The average carbon content of the converter steel is 0.043%, and the proportion of low-carbon steel smelting is relatively large. The traditional furnace repair process used before was sand repair. According to the furnace age, the furnace was repaired 1 to 2 times per shift, and the furnace age of the re-blowing furnace was about 3,000 furnaces. After adopting the converter bottom blowing long-life and efficient maintenance technology, the converter sand repair furnace age was increased to 4,000 furnaces, and the air-permeable bricks were visible throughout the furnace service. After 6,000 furnaces, the bottom blowing flow rate can still reach 80 to 120Nm in the post-stirring stage. 3 / h·branch, the carbon-oxygen accumulation of the whole furnace service can be controlled within 0.0020, which has a significant effect on saving auxiliary materials and steel materials, and the combined blowing furnace life can reach more than 8000.

[0066] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A long-life and efficient maintenance method for bottom blowing of a converter, characterized in that: By adjusting the processes and combinations of converter slag splashing, slag adjustment, slag filling and sand filling during the service life, the converter bottom blowing can be maintained for a long life and high efficiency, so that the converter bottom blowing life and converter life can be synchronized; The process and combined process methods for converter slag splashing, slag adjustment, slag filling and sand filling during the service life are as follows: S1, 1 to 500 furnaces, start from the first furnace to splash slag to protect the furnace; S2, 500 ~ 1000 furnace, slag splashing and slag adjustment and slag splashing are combined; S3, 1000-2000 furnace, slag adjustment, slag splashing and slag filling are combined; S4, 2000 ~ 3000 furnace, slag adjustment, slag splashing and slag filling are combined; S5, 3000 ~ 4000 furnace, slag adjustment and slag splashing, slag filling and sand filling are combined; In S6, 4000-5000 furnace, a combination of non-reversing slag splashing, slag adjustment and slag splashing, and sand filling is carried out; In S7, 5000-6000 furnace, a combination of non-reversing slag splashing, slag adjustment and slag splashing, and sand filling is carried out; In S8, 6000-7000 furnace, a combination of non-reversing slag splashing, slag adjustment and slag splashing, and sand filling is carried out; In the furnace of S9, 7000-8000, a combination of slag splashing without pouring slag, slag adjustment and slag splashing, and sand filling is carried out; In S10, 8000-9000 furnace, slag adjustment, slag splashing, slag filling and sand filling are combined; In the furnaces S11, 9000-11000, slag adjustment, slag splashing and sand filling are combined.

2. The long-life and high-efficiency maintenance method for bottom blowing of a converter according to claim 1 is characterized in that: In step S1, the slag splashing process is: pouring the slag first and then splashing the slag, and the amount of slag poured is 40% to 60%; In step S2, the slag adjustment and slag splashing process is: first pouring slag, then adjusting slag and then splashing slag, the slag pouring amount is 40% to 60%, the slag adjustment slag amount is 2 to 4 kg / ton of steel, and the slag adjustment slag is at least one or two of lime or dolomite; the slag adjustment and slag splashing frequency is 1 to 2 times / shift; In the step S3, the slag adjustment and slag splashing process is: first pouring slag, then adjusting slag and then splashing slag, the slag pouring amount is 30% to 50%, the slag adjustment slag amount is 3 to 6 kg / t per ton of steel, and the slag adjustment slag is at least one or two of lime or dolomite; the slag filling process is: without pouring slag, adding one or two of lime or dolomite for slag adjustment and slag filling, the slag adjustment material is at least one or two of lime or dolomite; the amount of slag adjustment material added is 5 to 10 kg / t; the slag filling frequency is 1 time / 48 hours; the slag filling time is 20 to 40 minutes; In the step S4, the slag adjustment and slag splashing process is: first pouring slag, then adjusting slag and then splashing slag, the slag pouring amount is 40% to 50%, the slag adjustment slag amount is 3 to 6 kg / t per ton of steel, and the slag adjustment slag is at least one or two of lime or dolomite; the slag filling process is: without pouring slag, adding one or two of lime or dolomite for slag adjustment and slag filling, the slag adjustment material is at least one or two of lime or dolomite; the amount of slag adjustment material added is 5 to 10 kg / t; the slag filling frequency is 1 time / 24 hours; the slag filling time is 20 to 40 minutes; In step S5, the sand filling process is as follows: pour out the slag in the furnace and add the filling material to fill the furnace, the filling material is asphalt-based filling material; the amount of filling material added is 5-7 kg / t; the frequency of sand filling is once / 48 hours; the sand filling time is 20-30 minutes; In step S6, the slag adjustment and slag splashing process is: after the steel tapping is completed, the slag is adjusted and then splashed, the slag material amount of the slag adjustment is 5-8kg / t of ton steel, the slag material of the slag adjustment is at least one or two of lime or dolomite, the slag splashing without slag pouring is performed 1-2 times per shift, the slag replenishment frequency of the slag splashing without slag pouring is 1 time / 24 hours, and the slag replenishment time is 15 minutes; the remaining furnaces are performed after slag pouring and slag splashing; the sand replenishment frequency is 1 time / 48 hours; In step S7, the slag adjustment and slag splashing process is: after the steel tapping is completed, the slag is adjusted and then splashed, the slag material amount of the slag adjustment is 5-8kg / t of steel, the slag material of the slag adjustment is at least one or two of lime or dolomite, and the slag splashing without slag pouring is performed 2-3 times per shift; the slag replenishment frequency of the slag splashing without slag pouring is 1 time / 12 hours, and each slag replenishment lasts 15 minutes; the remaining furnaces perform slag splashing after slag pouring; the sand replenishment frequency is 1 time / 36 hours; In step S8, the slag adjustment and slag splashing process is: after the steel tapping is completed, the slag is adjusted and then splashed, the slag material amount of the slag adjustment is 5-8kg / t of steel, the slag material of the slag adjustment is at least one or two of lime or dolomite, and the slag splashing without slag pouring is performed 3-4 times per shift; the slag replenishment frequency of the slag splashing without slag pouring is 1 time / 8 hours, and the slag replenishment time is 15 minutes; the remaining furnaces are performed after slag pouring and slag splashing; the sand replenishment frequency is 1 time / 24 hours; In step S9, the slag adjustment and slag splashing process is: after the steel tapping is completed, the slag is adjusted and then splashed, the slag material amount of the slag adjustment is 5-8kg / t of steel, the slag material of the slag adjustment is at least one or two of lime or dolomite, and the slag splashing without slag pouring is performed 4-6 times per shift; the slag replenishment frequency of the slag splashing without slag pouring is 1 time / 6 hours, and each slag replenishment lasts 15 minutes; the remaining furnaces perform slag splashing after slag pouring; the sand replenishment frequency is 1 time / 12 hours; In the step S10, the slag filling frequency is once every 12 hours; the sand filling frequency is once every 8 hours; In the step S11, the frequency of sand replenishment is once every 4 hours.

3. The long-life and high-efficiency maintenance method for bottom blowing of a converter according to claim 1 or 2, characterized in that: The process of bottom blowing gas supply for slag adjustment and splashing is as follows: bottom blowing flow rate is 70~100Nm 3 / h·branch, bottom blowing time t=T+30s, where T is the top blowing nitrogen splashing time.

4. The long-life and high-efficiency maintenance method for bottom blowing of a converter according to claim 1 or 2, characterized in that: The process of slag filling bottom blowing gas supply is: 0~10min, bottom blowing flow rate is 30~40Nm 3 / h·Branch; 10~20min, bottom blowing flow rate is 40~50Nm 3 / h·Branch; 20~30min, bottom blowing flow rate is 50~70Nm 3 / h·branch.

5. The converter bottom blowing longevity and high efficiency maintenance method according to claim 1 or 2, characterized in that: The process of sand filling bottom blowing air supply is: 0~10min, bottom blowing flow rate is 20~30Nm 3 / h·Branch; 10~20min, bottom blowing flow rate is 30~40Nm 3 / h·Branch; 20~30min, bottom blowing flow rate is 40~60Nm 3 / h·branch.

6. The long-life and high-efficiency maintenance method for bottom blowing of a converter according to claim 1 or 2, characterized in that: In the step S11, the process of sand filling in the furnace once every 4 hours at 9000-11000 is: slag adjustment and slag splashing - sand filling.

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