Heat preservation covering agent for blast furnace tapping large channel and use method of heat preservation covering agent

Abstract

The invention provides a heat-preservation covering agent for a blast furnace tapping large channel and a use method of the heat-preservation covering agent. The heat-preservation covering agent comprises blast furnace cloth bag ash and a heat-preservation auxiliary material, the heat preservation auxiliary material comprises coal gangue or coke powder. According to the method, the blast furnace cloth bag ash and a certain amount of heat preservation auxiliary materials are added, the characteristic that carbon in the blast furnace cloth bag ash and the heat preservation auxiliary materials is easy to burn is reasonably utilized, the blast furnace cloth bag ash and the heat preservation auxiliary materials are added into the blast furnace tapping main channel for heat preservation in a balanced dosage, and the blast furnace cloth bag ash and the heat preservation auxiliary materials are used for replacing outsourced heat preservation agents for heat preservation of the tapping main channel. The iron-making production cost can be reduced, meanwhile, the treatment cost of solid waste cloth bag ash and coal gangue is reduced, the heat preservation effect is stabilized, meanwhile, part of iron elements in the cloth bag ash are recycled, and the blast furnace molten iron yield is increased.

Description

Technical Field

[0001] The invention belongs to the technical field of iron and steel metallurgy and resource recycling, and particularly relates to a thermal insulation covering agent for a blast furnace tapping ditch and a use method thereof. Background Art

[0002] Ironmaking is the process of extracting metallic iron from iron-containing minerals (mainly iron oxides). There are mainly blast furnace method, direct reduction method, molten reduction method and plasma method. It is an important link in steel production. Blast furnace ironmaking is widely used because of its good technical and economic indicators, simple process, large production volume, high labor productivity and low energy consumption. The iron produced by this method accounts for more than 95% of the world's total iron production.

[0003] Blast furnace smelting is a continuous production process of reducing iron ore into pig iron. During production, iron ore, coke, and flux are continuously loaded from the top of the furnace (generally, the top of the furnace is composed of a bell and a hopper, and the modern blast furnace is a bell-valve furnace top and a bell-free furnace top), hot air (1000-1300 degrees Celsius) is blown in from the tuyere at the bottom of the blast furnace, and fuels such as oil, coal or natural gas are sprayed in. The iron ore loaded into the blast furnace is mainly a compound of iron and oxygen. At high temperature, the coke neutralizes the carbon in the injection material and the carbon monoxide generated by the combustion of carbon to undergo a reduction reaction, and the oxygen in the iron ore is taken out to obtain iron. Pig iron is smelted from the iron ore through a reduction reaction, and molten iron is released from the iron outlet.

[0004] During the blast furnace smelting process, the blast furnace tapping ditch is the channel for high-temperature molten iron and slag to flow out from the tapping hole, and it is also the place for slag and iron separation. More specifically, due to the high density of molten iron and the low density of slag, the slag gradually floats on the upper layer of the ditch, and the molten iron sinks to the lower layer of the ditch. The slag enters the blast furnace water-slag system through the slag ditch, and the molten iron is further separated by the slag skimmer and flows into the dragon ditch, and then flows into the molten iron tank from the dragon ditch.

[0005] During the steel production process, after the blast furnace plugging operation is completed, the iron slag in the blast furnace tapping channel is emptied. The interval between the next tapping and the tapping is long, so a large amount of insulation is needed to cover the surface of the tapping channel for insulation. This ensures that when the blast furnace tapping is opened for the next batch, the high-temperature iron retains sufficient heat and maintains good fluidity, thereby achieving the smooth separation of the high-temperature slag and molten iron.

[0006] Therefore, it is necessary to provide a low-cost and environmentally friendly thermal insulation covering agent to achieve effective thermal insulation of the iron-outlet ditch. Summary of the invention

[0007] In view of the shortcomings of the prior art, the purpose of the present invention is to provide a blast furnace iron-outlet ditch insulation covering agent and a method of using the same. The present invention adds blast furnace bag ash and a certain amount of insulation auxiliary materials, reasonably utilizes the easy combustion characteristics of carbon in the blast furnace bag ash and insulation auxiliary materials, balances the amount of addition to the blast furnace iron-outlet ditch for insulation, and uses blast furnace bag ash and insulation auxiliary materials instead of purchased insulation agents to insulate the iron-outlet ditch, which can reduce the ironmaking production cost, while reducing the processing cost of solid waste bag ash and coal gangue, while stabilizing the insulation effect, recovering part of the iron element in the bag ash, and increasing the blast furnace molten iron output.

[0008] In order to achieve the purpose of the invention, the present invention adopts the following technical solutions:

[0009] In a first aspect, the present invention provides a thermal insulation covering agent for a blast furnace tapping groove, the thermal insulation covering agent comprising blast furnace bag ash and thermal insulation auxiliary materials;

[0010] The auxiliary heat-insulating material includes coal gangue or coke powder.

[0011] The blast furnace tapping groove insulation covering agent of the present invention is divided into two types, one is a mixture of blast furnace bag ash and coal gangue; the other is a mixture of blast furnace bag ash and coke powder;

[0012] The present invention uses blast furnace bag ash and insulation auxiliary materials (coal gangue and coke powder) as the main materials of the insulation covering agent for insulation, thereby realizing the transformation of waste into treasure; the insulation covering agent provided by the present invention is used instead of the purchased insulation agent, which can stabilize the insulation effect of the iron-outlet ditch while meeting the production needs and reducing the production cost.

[0013] As a preferred technical solution of the present invention, the iron content in the blast furnace bag ash is ≥40wt%, for example, it can be 40wt%, 42wt%, 44wt%, 46wt%, 48wt% or 50wt%, etc., but is not limited to the listed values, and other values ​​not listed within the numerical range are also applicable.

[0014] More specifically, the main components of the blast furnace bag ash include elements such as iron, carbon, zinc, potassium, sodium and carbon, among which the iron content exceeds 40wt% and the carbon content is above 20wt%; the contents of zinc, potassium, sodium and other elements are also relatively high. The blast furnace bag ash is obtained through dry dust removal during the blast furnace smelting process, along with the raw material dust carried by the blast furnace gas and the violent reaction in the high temperature zone. Due to its small particle size and light specific gravity, it is easy to float in the air, causing environmental pollution, and it is easy to spontaneously combust when it does not come into contact with the air; in addition, the blast furnace bag ash is highly corrosive, contains alkali metals and alkaline earth metals, and is easy to react with water to form alkaline compounds. When processing the blast furnace bag ash, it is usually pelletized and returned to the blast furnace for use again, but due to the limitation of the sodium, potassium and zinc content, when their proportions reach a certain level, they can no longer be returned to the blast furnace system, otherwise the ash will cause furnace nodules or damage the refractory materials;

[0015] The present invention uses the blast furnace bag ash as raw material, realizes the transformation of waste into treasure, and further makes the blast furnace iron-outlet ditch thermal insulation covering agent a green product.

[0016] In addition, the blast furnace bag ash of the present invention contains a relatively high content of iron. During the heat preservation treatment process, the iron in the blast furnace bag ash melts into the molten iron at a high temperature, thereby increasing the output of the blast furnace molten iron.

[0017] Preferably, the particle size of the blast furnace bag ash is ≤10 mm, for example, it can be 10 mm, 9 mm, 8 mm, 7 mm, 6 mm or 5 mm, but is not limited to the listed values, and other values ​​not listed within the numerical range are also applicable.

[0018] As a preferred technical solution of the present invention, the particle size of the coal gangue is ≤15mm, for example, it can be 15mm, 14mm, 13mm, 12mm, 11mm or 10mm, but is not limited to the listed values, and other values ​​not listed within the numerical range are also applicable.

[0019] Preferably, the carbon content of the coal gangue is ≥30wt%, for example, it can be 30wt%, 31wt%, 32wt%, 33wt%, 34wt% or 35wt%, etc., but is not limited to the listed values, and other values ​​not listed within the numerical range are also applicable.

[0020] It is worth noting that the coal gangue described in the present invention is solid waste discharged during the coal mining and coal washing process. It is a kind of black-gray rock with a low carbon content and harder than coal that is associated with the coal seam during the coal formation process. If the coal gangue is abandoned, it will occupy a large area of ​​land; and the sulfide in the coal gangue will escape or leach and pollute the atmosphere, farmland and water bodies. A large amount of coal gangue accumulation will also spontaneously combust and cause fires, or collapse in the rainy season, silting up rivers and causing disasters.

[0021] The invention uses the coal gangue as raw material to realize resource utilization of solid waste.

[0022] As a preferred technical solution of the present invention, the mass ratio of the coal gangue to the blast furnace bag ash is 1-5:2-10, for example, it can be 1:2, 1:4, 1:6, 1:8, 1:10, 3:2, 4:2 or 5:2, but is not limited to the listed values, and other values ​​not listed within the numerical range are also applicable.

[0023] As a preferred technical solution of the present invention, the content of coal gangue in the blast furnace iron-tapping ditch insulation covering agent is ≥20wt%, for example, it can be 20wt%, 25wt%, 30wt%, 35wt%, 40wt% or 45wt%, etc., but is not limited to the listed values, and other values ​​not listed within the numerical range are also applicable; preferably 33.3wt%.

[0024] It is worth noting that a low content of coal gangue in the thermal insulation covering agent for the blast furnace tapping ditch of the present invention will lead to a reduction in the thermal insulation effect.

[0025] As a preferred technical solution of the present invention, the particle size of the coke powder is ≤10 mm, for example, it can be 10 mm, 9 mm, 8 mm, 7 mm, 6 mm or 5 mm, but is not limited to the listed values, and other values ​​not listed within the numerical range are also applicable.

[0026] In the present invention, the coke powder is coke powder under the blast furnace trough, and its carbon content is not less than 70wt%. In the high temperature environment of the blast furnace iron-outlet ditch, the carbon in the mixture formed by mixing the blast furnace bag ash and the coke powder burns slowly, and heat is released during the combustion process, thereby achieving the insulation effect on the blast furnace iron-outlet ditch.

[0027] As a preferred technical solution of the present invention, the volume ratio of the coke powder to the blast furnace bag ash is 1-4:1-8, for example, it can be 1:8, 1:7, 1:6, 1:5, 1:4, 1:3, 1:2, 1:1, 2:1, 3:1 or 4:1, but is not limited to the listed values, and other values ​​not listed within the numerical range are also applicable.

[0028] Preferably, the coke powder content in the blast furnace iron-outlet ditch insulation covering agent is ≥12.5 vol%, for example, it can be 12.5 vol%, 13 vol%, 13.5 vol%, 14 vol% or 14.5 vol%, etc., but is not limited to the listed values, and other values ​​not listed within the numerical range are also applicable.

[0029] Preferably, the coke powder content in the blast furnace iron-outlet ditch insulation covering agent is 12.5-25 vol%, for example, it can be 12.5 vol%, 15 vol%, 17 vol%, 19 vol%, 20 vol%, 21 vol%, 22 vol%, 23 vol%, 24 vol% or 25 vol%, but is not limited to the listed values, and other values ​​not listed within the numerical range are also applicable.

[0030] In the present invention, when the coke powder content in the thermal insulation covering agent of the blast furnace tapping groove is relatively small, the carbon content in the thermal insulation covering agent is reduced, thereby resulting in a decrease in the thermal insulation effect.

[0031] In a second aspect, the present invention provides a method for using the thermal insulation covering agent for the large groove of the blast furnace iron-making process as described in the first aspect, and the method for using the thermal insulation covering agent for the large groove of the blast furnace iron-making process comprises:

[0032] After the blast furnace is plugged, it is left to stand for cooling and then the blast furnace tapping groove insulation covering agent is covered on the surface of the blast furnace tapping groove for insulation treatment.

[0033] As a preferred technical solution of the present invention, the time for the static cooling treatment is 6 to 8 minutes, for example, it can be 6 minutes, 6.4 minutes, 6.8 minutes, 7.2 minutes, 7.6 minutes or 8 minutes, but is not limited to the listed values, and other values ​​not listed within the numerical range are also applicable.

[0034] In the present invention, the time of the static cooling treatment is 6 to 8 minutes. The static cooling treatment can form a solid isolation layer on the surface of the liquid in the blast furnace iron-outlet groove to carry the thermal insulation covering agent. If the time of the static cooling treatment is too short, the thermal insulation covering agent of the blast furnace iron-outlet groove will be precipitated to the bottom of the blast furnace iron-outlet groove. If the time of the static cooling treatment is too long, the heat loss of the blast furnace iron-outlet groove will increase.

[0035] As a preferred technical solution of the present invention, the covering thickness of the blast furnace iron-outlet ditch insulation covering agent is 2 to 4 cm, for example, it can be 2 cm, 2.4 cm, 2.8 cm, 3.2 cm, 3.6 cm or 4 cm, but is not limited to the listed values, and other values ​​not listed within the numerical range are also applicable.

[0036] In the present invention, the amount of thermal insulation covering agent used on the surface of the blast furnace iron-outlet groove is guaranteed by limiting the covering thickness; if the covering thickness is too thick, more thermal insulation covering agent will remain on the surface of the blast furnace iron-outlet groove when the blast furnace is tapping iron, and the remaining thermal insulation covering agent will absorb more heat in the blast furnace slag to carry out an exothermic reaction of carbon combustion, thereby affecting the fluidity of the blast furnace slag; if the covering thickness is too thin, the thermal insulation capacity will be reduced.

[0037] The numerical range described in the present invention not only includes the point values ​​listed above, but also includes any point values ​​between the above numerical ranges that are not listed. Due to space limitations and for the sake of simplicity, the present invention no longer exhaustively lists the specific point values ​​included in the range.

[0038] Compared with the prior art, the present invention has the following beneficial effects:

[0039] (1) The present invention can achieve effective insulation of the blast furnace tapping groove by mixing blast furnace bag ash and insulation auxiliary materials in a certain proportion, replacing the use of purchased insulation agents for the blast furnace tapping groove. The insulation effect of the blast furnace tapping groove insulation covering agent of the present invention can not only meet production needs, but also effectively reduce production costs;

[0040] (2) The present invention uses solid waste as raw material, turning waste into treasure, and the blast furnace iron-outlet ditch insulation covering agent of the present invention is a green product;

[0041] (3) The blast furnace bag ash used in the blast furnace iron-tapping ditch insulation covering agent of the present invention contains a relatively high content of iron. During the blast furnace iron-tapping process, part of the iron in the bag ash melts into the molten iron at a high temperature, thereby increasing the output of molten iron in the blast furnace. DETAILED DESCRIPTION

[0042] The technical solution of the present invention is further described below by specific implementation methods. It should be understood by those skilled in the art that the embodiments are only to help understand the present invention and should not be regarded as specific limitations of the present invention.

[0043] Example 1

[0044] This embodiment provides a blast furnace tapping groove insulation covering agent, the insulation covering agent includes blast furnace bag ash and coal gangue;

[0045] The iron content of the blast furnace bag ash is 45wt% and the particle size is ≤8mm;

[0046] The particle size of the coal gangue is ≤12mm; the carbon content is 35wt%;

[0047] The content of coal gangue in the thermal insulation covering agent for the blast furnace tapping ditch is 33.3wt%.

[0048] The method for using the above-mentioned blast furnace tapping groove insulation covering agent comprises: after plugging the blast furnace, standing for cooling treatment for 7 minutes, and then covering the blast furnace tapping groove insulation covering agent on the surface of the blast furnace tapping groove for insulation treatment;

[0049] The covering thickness of the blast furnace iron-outlet ditch thermal insulation covering agent is 3 cm.

[0050] Example 2

[0051] This embodiment provides a blast furnace tapping groove insulation covering agent, the insulation covering agent includes blast furnace bag ash and coal gangue;

[0052] The iron content of the blast furnace bag ash is 40wt% and the particle size is ≤10mm;

[0053] The particle size of the coal gangue is ≤15mm; the carbon content is 30wt%;

[0054] The content of coal gangue in the thermal insulation covering agent for the blast furnace tapping groove is 20wt%.

[0055] The method for using the above-mentioned blast furnace tapping groove insulation covering agent comprises: after plugging the blast furnace, standing for cooling treatment for 8 minutes, and then covering the blast furnace tapping groove insulation covering agent on the surface of the blast furnace tapping groove for insulation treatment;

[0056] The covering thickness of the blast furnace iron-outlet ditch thermal insulation covering agent is 2 cm.

[0057] Example 3

[0058] This embodiment provides a blast furnace tapping groove insulation covering agent, the insulation covering agent includes blast furnace bag ash and coal gangue;

[0059] The iron content of the blast furnace bag ash is 42wt% and the particle size is ≤5mm;

[0060] The particle size of the coal gangue is ≤10mm; the carbon content is 36wt%;

[0061] The content of coal gangue in the thermal insulation covering agent for the blast furnace tapping groove is 15wt%.

[0062] The method for using the above-mentioned blast furnace tapping groove insulation covering agent comprises: after plugging the blast furnace, standing and cooling for 6 minutes, and then covering the blast furnace tapping groove insulation covering agent on the surface of the blast furnace tapping groove for insulation treatment;

[0063] The covering thickness of the blast furnace iron-outlet ditch thermal insulation covering agent is 2 cm.

[0064] Example 4

[0065] This embodiment provides a blast furnace tapping groove insulation covering agent, the insulation covering agent is different from the embodiment 1 only in that:

[0066] In this embodiment, the particle size of the blast furnace bag ash is adjusted to 15-20 mm.

[0067] The method of using the above-mentioned blast furnace iron-outlet ditch thermal insulation covering agent is the same as that in Example 1.

[0068] Example 5

[0069] This embodiment provides a blast furnace tapping groove insulation covering agent, the insulation covering agent is different from the embodiment 1 only in that:

[0070] In this embodiment, the particle size of the coal gangue is adjusted to 20-30 mm.

[0071] The method of using the above-mentioned blast furnace iron-outlet ditch thermal insulation covering agent is the same as that in Example 1.

[0072] Example 6

[0073] This embodiment provides a blast furnace tapping groove insulation covering agent, the insulation covering agent is different from the embodiment 1 only in that:

[0074] In this embodiment, the content of coal gangue in the thermal insulation covering agent of the blast furnace tapping groove is adjusted to 5wt%.

[0075] The method of using the above-mentioned blast furnace iron-outlet ditch thermal insulation covering agent is the same as that in Example 1.

[0076] Example 7

[0077] This embodiment provides a blast furnace tapping groove insulation covering agent, the insulation covering agent includes blast furnace bag ash and coke powder;

[0078] The iron content of the blast furnace bag ash is 45wt% and the particle size is 5-10mm;

[0079] The particle size of the coke powder is 4 to 10 mm;

[0080] The coke powder content in the blast furnace tapping groove thermal insulation covering agent is 20 vol%.

[0081] The method for using the above-mentioned blast furnace tapping groove insulation covering agent comprises: after plugging the blast furnace, standing and cooling for 6 minutes, and then covering the blast furnace tapping groove insulation covering agent on the surface of the blast furnace tapping groove for insulation treatment;

[0082] The covering thickness of the blast furnace iron-outlet ditch thermal insulation covering agent is 3 cm.

[0083] Example 8

[0084] This embodiment provides a blast furnace tapping groove insulation covering agent, the insulation covering agent includes blast furnace bag ash and coke powder;

[0085] The iron content of the blast furnace bag ash is 40wt% and the particle size is 5-8mm;

[0086] The particle size of the coke powder is 4 to 6 mm;

[0087] The coke powder content in the blast furnace tapping groove insulation covering agent is 12.5 vol%.

[0088] The method for using the above-mentioned blast furnace tapping groove insulation covering agent comprises: after plugging the blast furnace, standing for cooling treatment for 8 minutes, and then covering the blast furnace tapping groove insulation covering agent on the surface of the blast furnace tapping groove for insulation treatment;

[0089] The covering thickness of the blast furnace iron-outlet ditch thermal insulation covering agent is 4 cm.

[0090] Example 9

[0091] This embodiment provides a blast furnace tapping groove insulation covering agent, the insulation covering agent includes blast furnace bag ash and coke powder;

[0092] The iron content of the blast furnace bag ash is 50wt% and the particle size is 1-5mm;

[0093] The particle size of the coke powder is 1 to 5 mm;

[0094] The coke powder content in the blast furnace tapping groove insulation covering agent is 12.5 vol%.

[0095] The method for using the above-mentioned blast furnace tapping groove insulation covering agent comprises: after plugging the blast furnace, standing and cooling for 6 minutes, and then covering the blast furnace tapping groove insulation covering agent on the surface of the blast furnace tapping groove for insulation treatment;

[0096] The covering thickness of the blast furnace iron-outlet ditch thermal insulation covering agent is 2 cm.

[0097] Example 10

[0098] This embodiment provides a blast furnace tapping groove insulation covering agent, the insulation covering agent is different from that of embodiment 7 only in that:

[0099] The particle size of the coke powder in this embodiment is adjusted to 10-20 mm.

[0100] The method of using the above-mentioned blast furnace iron-outlet ditch thermal insulation covering agent is the same as that in Example 7.

[0101] Embodiment 11

[0102] This embodiment provides a blast furnace tapping groove insulation covering agent, the insulation covering agent is different from that of embodiment 7 only in that:

[0103] In this embodiment, the coke powder content in the thermal insulation covering agent of the blast furnace tapping groove is adjusted to 5 vol%.

[0104] Example 12

[0105] This embodiment provides a thermal insulation covering agent for a large iron-outlet groove of a blast furnace, and the thermal insulation covering agent is the same as that of Embodiment 7.

[0106] The method for using the above-mentioned blast furnace tapping groove insulation covering agent is different from that of Example 7 only in that:

[0107] In this embodiment, the time of the static cooling treatment is adjusted to 5 minutes.

[0108] Embodiment 13

[0109] This embodiment provides a thermal insulation covering agent for a large iron-outlet groove of a blast furnace, and the thermal insulation covering agent is the same as that of Embodiment 7.

[0110] The method for using the above-mentioned blast furnace tapping groove insulation covering agent is different from that of Example 7 only in that:

[0111] In this embodiment, the time of the static cooling treatment is adjusted to 10 minutes.

[0112] Embodiment 14

[0113] This embodiment provides a thermal insulation covering agent for a large iron-outlet groove of a blast furnace, and the thermal insulation covering agent is the same as that of Embodiment 7.

[0114] The method for using the above-mentioned blast furnace tapping groove insulation covering agent is different from that of Example 7 only in that:

[0115] In this embodiment, the covering thickness of the blast furnace tapping groove insulation covering agent is adjusted to 0.5 cm.

[0116] Embodiment 15

[0117] This embodiment provides a thermal insulation covering agent for a large iron-outlet groove of a blast furnace, and the thermal insulation covering agent is the same as that of Embodiment 7.

[0118] The method for using the above-mentioned blast furnace tapping groove insulation covering agent is different from that of Example 7 only in that:

[0119] In this embodiment, the covering thickness of the blast furnace iron-outlet ditch thermal insulation covering agent is adjusted to 5.5 cm.

[0120] Comparative Example 1

[0121] This comparative example provides a thermal insulation covering agent for a blast furnace tapping ditch, wherein the thermal insulation covering agent is blast furnace bag ash with an iron content of 45wt% and a particle size of 5-10mm.

[0122] The method of using the above-mentioned blast furnace iron-outlet ditch thermal insulation covering agent is the same as that in Example 7.

[0123] Comparative Example 2

[0124] This comparative example provides a thermal insulation covering agent for a large iron-outlet groove of a blast furnace, wherein the thermal insulation covering agent is coke powder with a particle size of 4 to 10 mm.

[0125] The method of using the above-mentioned blast furnace iron-outlet ditch thermal insulation covering agent is the same as that in Example 7.

[0126] Comparative Example 3

[0127] This comparative example provides a thermal insulation covering agent for a large iron-outlet groove of a blast furnace. The thermal insulation covering agent is coal gangue with a particle size of ≤12 mm and a carbon content of 35 wt%.

[0128] The method of using the above-mentioned blast furnace iron-outlet ditch thermal insulation covering agent is the same as that in Example 7.

[0129] Comparative Example 4

[0130] This comparative example provides a blast furnace tapping ditch insulation covering agent, wherein the insulation covering agent is a mixture of blast furnace bag ash with a particle size of ≤8mm, coal gangue with a particle size of ≤12mm, and coke powder with a particle size of 1-5mm;

[0131] The mass ratio of the blast furnace ash bag to coal gangue is 4:1; the volume ratio of the blast furnace ash bag to coke powder is 7:1;

[0132] The method of using the above-mentioned blast furnace iron-outlet ditch thermal insulation covering agent is the same as that in Example 7.

[0133] The insulation test was conducted on the blast furnace tapping groove insulation covering agent provided in the above embodiments and comparative examples, and the results are shown in Table 1;

[0134] The insulation test specifically includes: testing the time it takes for the temperature of the blast furnace iron-outlet ditch to drop to 850°C; wherein the initial temperature of the blast furnace iron-outlet ditch is 1350°C.

[0135] Table 1

[0136]

[0137]

[0138] According to Table 1, we can know the following points:

[0139] (1) Comprehensive analysis of Examples 1-3 and Examples 7-9 shows that the blast furnace tapping groove insulation covering agent provided by the present invention has excellent insulation effect and can turn waste into treasure;

[0140] (2) Comprehensive analysis of Examples 1, 4-6, 7, 10-11 shows that the selection of the raw material particle size range of the blast furnace tapping groove insulation covering agent and the control of the raw material content will affect the insulation effect of the insulation covering agent;

[0141] The larger particle size of the raw material of the thermal insulation covering agent and the decrease in the content of coke powder or coal gangue will lead to a decrease in the thermal insulation effect of the thermal insulation covering agent;

[0142] (3) Comprehensive analysis of Example 7 and Examples 12-15 shows that the use method of the blast furnace tapping groove insulation covering agent will also affect its insulation effect;

[0143] When the static cooling treatment time is too short, an isolation layer cannot be formed on the surface of the blast furnace tapping groove, causing part of the thermal insulation covering agent to sink to the bottom of the groove, thereby reducing the thermal insulation effect. In addition, when the static cooling treatment time is too long, the large groove will lose more heat, and the thermal insulation covering agent will not be completely burned, thereby reducing the thermal insulation effect.

[0144] When the thickness of the thermal insulation covering agent is too thick, the covering agent will not burn completely, and the thermal insulation effect will also decrease; on the contrary, the thickness is too thin, the covering agent will release less heat during combustion, and the thermal insulation effect will decrease;

[0145] (4) Comprehensive analysis of Examples 1, 7 and Comparative Examples 1-4 shows that the selection of raw materials for the blast furnace tapping groove insulation covering agent will affect the insulation effect;

[0146] In addition, the coke powder has a high carbon content and has the best insulation effect on the blast furnace iron-outlet ditch, but due to its high price, it is not suitable for industrial application.

[0147] In summary, the present invention adds blast furnace bag ash and a certain amount of thermal insulation auxiliary materials, reasonably utilizes the easy-to-burn property of carbon in blast furnace bag ash and thermal insulation auxiliary materials, balances the dosage and adds them to the blast furnace iron-outlet ditch for insulation, and uses blast furnace bag ash and thermal insulation auxiliary materials instead of purchased thermal insulation agents to insulate the iron-outlet ditch, thereby reducing the iron-making production cost and the processing cost of solid waste bag ash and coal gangue, while stabilizing the thermal insulation effect, recovering part of the iron element in the bag ash and increasing the blast furnace molten iron output.

[0148] The applicant declares that the specific embodiments described above further illustrate the objectives, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above description is only a specific embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A blast furnace tapping groove insulation covering agent, characterized in that: The thermal insulation covering agent includes blast furnace bag ash and thermal insulation auxiliary materials; The auxiliary heat-insulating material includes coal gangue or coke powder.

2. The blast furnace tapping groove thermal insulation covering agent according to claim 1, characterized in that: The iron content in the blast furnace bag ash is ≥40wt%; Preferably, the particle size of the blast furnace bag ash is ≤10 mm.

3. The blast furnace tapping groove thermal insulation covering agent according to claim 1, characterized in that: The particle size of the coal gangue is ≤15mm; Preferably, the carbon content of the coal gangue is ≥30wt%.

4. The blast furnace tapping groove thermal insulation covering agent according to any one of claims 1 to 3, characterized in that: The mass ratio of the coal gangue to the blast furnace bag ash is 1-5:2-10.

5. The blast furnace tapping groove thermal insulation covering agent according to claim 4, characterized in that: The content of coal gangue in the thermal insulation covering agent for the blast furnace tapping groove is ≥20wt%, preferably 33.3wt%.

6. The blast furnace tapping groove thermal insulation covering agent according to claim 2, characterized in that: The particle size of the coke powder is ≤10 mm.

7. The blast furnace tapping groove thermal insulation covering agent according to claim 6, characterized in that: The volume ratio of the coke powder to the blast furnace bag ash is 1-4:1-8; Preferably, the coke powder content in the blast furnace tapping ditch thermal insulation covering agent is ≥12.5 vol%; Preferably, the coke powder content in the blast furnace tapping ditch insulation covering agent is 12.5-25 vol%.

8. A method for using the blast furnace tapping groove thermal insulation covering agent according to any one of claims 1 to 7, characterized in that: The method for using the blast furnace tapping groove thermal insulation covering agent comprises: After the blast furnace is plugged, it is left to stand for cooling and then the blast furnace tapping groove insulation covering agent is covered on the surface of the blast furnace tapping groove for insulation treatment.

9. The method of use according to claim 8, characterized in that: The time for the static cooling treatment is 6 to 8 minutes.

10. The method of use according to claim 8 or 9, characterized in that: The covering thickness of the blast furnace tapping groove thermal insulation covering agent is 2 to 4 cm.

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