阅读说明：本技术 一种主沟渣铁分离器的制造工艺 (Manufacturing process of main channel iron slag separator ) 是由 王超 于 2020-05-19 设计创作，主要内容包括：本发明提供一种主沟渣铁分离器的制造工艺,包括以下步骤：混炼：将刚玉、碳化硅、碳素材料、超微粉、抗氧化剂和水搅拌混炼、得到混合物料；成型：将混合物料倒入预制模板中,待成型后脱模、得到坯料；烘烤烧制：将坯料放入隧道窑中烘烤烧制、得到分离器预制件；浇注：在主沟装模前将分离器预制件定位在预设位置,支模板,将分离器预制件与主沟一起浇注成型,得到与主沟相固定的主沟渣铁分离器；主沟渣铁分离器为一体式结构、具有烘烤烧制成型的分离器预制件、以及浇注在分离器预制件外周的浇注料外层。本申请涉及的主沟渣铁分离器具有抗渣性好、耐铁水冲刷、热震稳定性高等性能,具有较长的使用寿命,能够满足当前高炉快节奏生产的需要。(The invention provides a manufacturing process of a main channel iron slag separator, which comprises the following steps: mixing: stirring and mixing corundum, silicon carbide, carbon materials, superfine powder, an antioxidant and water to obtain a mixed material; molding: pouring the mixed material into a prefabricated template, and demolding after forming to obtain a blank; baking and firing: putting the blank into a tunnel kiln for baking and firing to obtain a separator prefabricated part; pouring: positioning the separator prefabricated part at a preset position before the main channel is filled with a mold, supporting a mold plate, and casting and molding the separator prefabricated part and the main channel together to obtain a main channel slag-iron separator fixed with the main channel; the main channel iron slag separator is of an integrated structure, and comprises a separator prefabricated member formed by baking and firing and a castable outer layer poured on the periphery of the separator prefabricated member. The main channel slag-iron separator has the advantages of good slag resistance, molten iron scouring resistance, high thermal shock stability and the like, has a long service life, and can meet the requirement of the current blast furnace on fast-paced production.)

1. A manufacturing process of a main channel slag-iron separator is characterized in that: the manufacturing process comprises the following steps:

s1, mixing: stirring and mixing the following raw material components according to the mass ratio to obtain a mixed material;

corundum: 70% -80%;

silicon carbide: 8% -14%;

carbon material: 2% -6%;

ultra-fine powder: 5% -8%;

antioxidant: 1% -3%;

water: 4% -6%;

s2, molding: pouring the mixed material into a prefabricated template, and demolding after forming to obtain a blank;

s3, baking and firing: putting the blank into a tunnel kiln for baking and firing to obtain a separator prefabricated part;

the separator preform has a stopper body, and a tapping channel separated by the stopper body, the tapping channel being located above the tapping channel;

when the blank is baked in the tunnel kiln, the temperature change rule in the tunnel kiln is as follows: raising the temperature from 0 ℃ to 1000 ℃ within 0-T1 hours, raising the temperature from 1000 ℃ to 1480 ℃ within T1-T2 hours, keeping the temperature at 1480 ℃ within T2-T3 hours, and lowering the temperature from 1480 ℃ to 0 ℃ within T3-T4 hours, wherein T1 is 20-24 hours, T2 is 28-30 hours, T3 is 20-24 hours, and T4 is 48-50 hours;

s4, pouring: positioning the separator prefabricated part at a preset position before a main channel is filled with a mold, supporting a mold plate, and casting and molding the separator prefabricated part and the main channel together to obtain a main channel slag-iron separator fixed with the main channel;

the main channel iron slag separator is of an integrated structure, is provided with a separator prefabricated member formed by baking and firing and a castable outer layer poured on the periphery of the separator prefabricated member.

2. The manufacturing process of claim 1, wherein: the carbon material is high-temperature asphalt.

3. The manufacturing process of claim 1, wherein: the superfine powder is a mixture of silicon dioxide and clay powder or a mixture of silicon oxide powder and clay powder, and the particle size of the superfine powder is not more than 5 um.

4. The manufacturing process of claim 1, wherein: the antioxidant is silicon carbide.

5. The manufacturing process of claim 1, wherein the substrate is a glass substrateThe method comprises the following steps: the volume density of the corundum is 2.79-2.81g/cm³。

6. The manufacturing process of claim 1, wherein: the pH value of the water is 6.6-7.5.

7. The manufacturing process of claim 1, wherein: in the step S2, the mixed material is molded in a prefabricated template, cured for 22-30 hours and demoulded.

Technical Field

The invention relates to the field of blast furnace ironmaking, in particular to a manufacturing process of a main channel slag-iron separator.

Background

In the blast furnace iron-making production process, the iron slag output by a blast furnace cast house flows into a main runner, the tail end of the main runner is provided with an iron slag separator (hereinafter, referred to as a main runner iron slag separator), the iron slag is separated into slag and molten iron after passing through the main runner iron slag separator, the slag flows into the slag runner, and the molten iron flows into the iron tapping runner and finally into a torpedo car. At present, a main channel slag-iron separator is mainly of a baffle type structure, and the floating slag is blocked by utilizing the difference of specific gravity of the slag and the molten iron, so that the molten iron only passes through the lower part, and the aim of separating the slag and the iron is fulfilled. Therefore, the main channel slag-iron separator is an important device for separating slag and molten iron in the blast furnace casting field, and plays an important role in improving the quality of the molten iron and prolonging the service life of the casting channel.

Furthermore, in the current main channel slag iron separator, during manufacturing, an intermediate body of the separator is manufactured in a high-temperature sintering mode, and then the intermediate body of the separator and a main channel liner are cast together. However, the main channel iron slag separator manufactured by the manufacturing process has the defect of short service life: in the iron-making production process, the influence of factors such as slag erosion, molten iron scouring and rapid cooling and heating is caused, the problem that the main channel slag-iron separator cast in situ by adopting a castable in the middle body of the separator cannot be well combined with the middle body of the separator sintered at high temperature and the outer layer of the newly-poured castable in the use process exists, and due to the fact that the expansion coefficients of the middle body of the separator and the outer layer of the castable are not consistent, the phenomena of separation and cracking of the middle body of the separator and the outer layer of the castable easily occur, even the main channel slag-iron separator is cracked or cracked, and therefore the phenomenon that the slag passes through an iron outlet channel is frequent. The torpedo car can be covered when the molten iron is seriously overflowed, and further the difficulty is brought to the next pretreatment procedure of the steelmaking molten iron.

Disclosure of Invention

In view of the above-mentioned drawbacks of the prior art, it is an object of the present invention to provide a process for manufacturing a main channel iron slag separator, which provides a long service life of the main channel iron slag separator.

In order to achieve the above object, the present invention provides a manufacturing process of a main channel iron slag separator, comprising the steps of:

s1, mixing: stirring and mixing the following raw material components according to the mass ratio to obtain a mixed material;

corundum: 70% -80%;

silicon carbide: 8% -14%;

carbon material: 2% -6%;

ultra-fine powder: 5% -8%;

antioxidant: 1% -3%;

water: 4% -6%;

s2, molding: pouring the mixed material into a prefabricated template, and demolding after forming to obtain a blank;

s3, baking and firing: putting the blank into a tunnel kiln for baking and firing to obtain a separator prefabricated part;

the separator preform has a stopper body, and a tapping channel separated by the stopper body, the tapping channel being located above the tapping channel;

when the blank is baked in the tunnel kiln, the temperature change rule in the tunnel kiln is as follows: raising the temperature from 0 ℃ to 1000 ℃ within 0-T1 hours, raising the temperature from 1000 ℃ to 1480 ℃ within T1-T2 hours, keeping the temperature at 1480 ℃ within T2-T3 hours, and lowering the temperature from 1480 ℃ to 0 ℃ within T3-T4 hours, wherein T1 is 20-24 hours, T2 is 28-30 hours, T3 is 20-24 hours, and T4 is 48-50 hours;

s4, pouring: positioning the separator prefabricated part at a preset position before a main channel is filled with a mold, supporting a mold plate, and casting and molding the separator prefabricated part and the main channel together to obtain a main channel slag-iron separator fixed with the main channel;

the main channel iron slag separator is of an integrated structure, is provided with a separator prefabricated member formed by baking and firing and a castable outer layer poured on the periphery of the separator prefabricated member.

Further, the carbon material is high-temperature asphalt.

Further, the superfine powder is a mixture of silicon dioxide and clay powder or a mixture of silicon oxide powder and clay powder, and the particle size of the superfine powder is not more than 5 um.

Further, the antioxidant is silicon carbide.

Further, the volume density of the corundum is 2.79-2.81g/cm³。

Further, the pH value of the water is 6.6-7.5.

Further, in the step S2, the mixed material is molded in a prefabricated template, cured for 22-30 hours, and then demolded.

As described above, the manufacturing process of the main channel iron slag separator according to the present invention has the following beneficial effects:

the main runner slag-iron separator has the advantages of being good in slag resistance, resistant to molten iron scouring, high in thermal shock stability and the like, long in service life, capable of meeting the requirements of current blast furnace fast-paced production, and capable of avoiding slag passing of an iron tapping runner, so that molten iron quality is ensured, and safe and efficient production of blast furnace iron making is guaranteed.

Drawings

FIG. 1 is a flow chart of the process of manufacturing a main channel iron slag separator of the present application.

Fig. 2 is a front view of a separator preform in the present application.

Fig. 3 is a side view of fig. 2.

FIG. 4 is a schematic view showing the temperature change of the tunnel kiln during baking and firing the green body.

FIG. 5 is a schematic view of the positioning of the separator preform in the main trench in the present application.

Description of the element reference numerals

10 separator preform

101 stop block body

102 slag discharge passage

103 tapping channel

20 main ditch

Detailed Description

The following description of the embodiments of the present invention is provided for illustrative purposes, and other advantages and effects of the present invention will become apparent to those skilled in the art from the present disclosure.

It should be understood that the structures, proportions, and dimensions shown in the drawings and described herein are for illustrative purposes only and are not intended to limit the scope of the present invention, which is defined by the claims, but rather by the claims. In addition, the terms such as "upper", "lower", "left", "right", "middle" and "one" used in the present specification are for convenience of description only and are not intended to limit the scope of the present invention, and changes or modifications of the relative relationship thereof may be made without substantial technical changes and modifications.

The application relates to the field of blast furnace iron making, in particular to a manufacturing process of a main channel slag-iron separator. In this embodiment, the main channel is parallel to the tapping channel, and the main channel is perpendicular to the tapping channel.

The manufacturing process of the main channel iron slag separator sequentially comprises the following steps:

step S1, kneading: stirring and mixing the following raw material components according to the mass ratio to obtain a mixed material;

corundum: 70% -80%;

silicon carbide: 8% -14%;

carbon material: 2% -6%;

ultra-fine powder: 5% -8%;

antioxidant: 1% -3%;

water: 4% -6%;

step S2, molding: and pouring the mixed material into a prefabricated template, and demolding after forming to obtain a blank.

Step S3, baking and firing: putting the blank into a tunnel kiln for baking and firing to obtain a separator prefabricated part 10; as shown in fig. 2 and 3, the separator preform 10 has a stopper body 101, and a tapping channel 102 and a tapping channel 103 separated by the stopper body 101, the tapping channel 102 being located above the tapping channel 103. The tapping channel 102 runs through the separator preform 10 in the direction of extension of the tapping channel, and the tapping channel 103 runs through the separator preform 10 in the direction of extension of the tapping channel. In addition, in this example, the width of the separator preform 10 was 550mm,The height is 800mm, the length is 1200mm, and the volume is 0.405g/cm³So as to reduce the refractory material and save the blast furnace ironmaking cost.

In particular, when the blank is baked and fired in a tunnel kiln, the temperature change rule in the tunnel kiln is as follows: as shown in FIG. 4, the temperature is raised from 0 ℃ to 1000 ℃ within 0-T1 hours, from 1000 ℃ to 1480 ℃ within T1-T2 hours, from 1480 ℃ at constant temperature within T2-T3 hours, and from 1480 ℃ to 0 ℃ within T3-T4 hours; 0-T1, baking with soft fire for 20-24 hr (T1 is 20-24 hr), usually not less than 20 hr; the interval of T1-T2 is medium-to-big fire baking, the time range of the medium-to-big fire baking is between 28 and 30 hours (namely T2 is 28 to 30 hours), and usually not less than 28 hours; the interval of T2-T3 is constant temperature baking, the time range of constant temperature baking is between 20-24 hours (namely T3 is 20-24 hours), usually not less than 20 hours; the interval of T3-T4 is temperature reduction baking, and the time range of temperature reduction baking is between 48 and 50 hours (namely T4 is between 48 and 50 hours), and is usually not less than 48 hours. Preferably, T1 is 20 hours, T2 is 30 hours, T3 is 20 hours, and T4 is 50 hours, i.e., the temperature change law in the tunnel kiln when the tunnel kiln bakes and fires the blank is as follows: heating from 0 deg.C to 1000 deg.C within 0-20 hr, heating from 1000 deg.C to 1480 deg.C within 20-50 hr, keeping at 1480 deg.C within 50-70 hr, and cooling from 1480 deg.C to 0 deg.C within 70-120 hr.

Step S4, pouring: positioning the separator preform 10 at a predetermined position, i.e., a position buried in the iron wire of the main trench 20, before the main trench 20 is filled with the mold, as shown in fig. 5; and then, supporting a template, and casting and molding the separator prefabricated part 10 and the main channel 20 together to obtain the main channel iron slag separator fixed with the main channel 20. The main channel iron slag separator is of an integrated structure, and comprises a separator prefabricated part 10 formed by baking and firing and a castable outer layer poured on the periphery of the separator prefabricated part 10.

The application relates to a main channel slag-iron separator which uses AL₂O₃-a separator with SiC-C as the main refractory; adding superfine powder to reduce porosity and improve slag resistance of the separator prefabricated part 10; adding antioxidant to improve the comprehensive oxidation resistance of refractory material, and pre-treating the separatorThe product 10 has the advantages of high strength, slag erosion resistance, molten iron erosion resistance and the like, and also has good thermal shock stability and oxidation resistance; particularly, the separator prefabricated part 10 is manufactured by adopting a baking and firing process, the temperature in the tunnel kiln is strictly controlled when blanks of the separator prefabricated part 10 are baked and fired, the separator prefabricated part 10 with high strength, good slag resistance, molten iron scouring resistance, high thermal shock stability and good oxidation resistance is finally obtained, the overall service life of the main runner iron and slag separator finally obtained after pouring is greatly prolonged, the effect of synchronous use with the high iron flux of the main runner 20 is achieved, the consumption of refractory materials is reduced, the cost of a steel mill is greatly saved, meanwhile, the requirement of the current high-speed-rhythm production of a blast furnace can be met, the slag passing phenomenon of an iron tapping runner is avoided, the quality of molten iron is ensured, and the safe and efficient production of blast furnace iron making is ensured. In addition, after the service life of the main channel iron slag separator is prolonged, the repair operation of the main channel iron slag separator in midway can be eliminated, and the labor intensity is reduced.

Further, with respect to the refractory selection aspect of the separator preform 10, the following preferred embodiments are provided.

Firstly, corundum: the main component of corundum is AL₂O₃Preferably, large-crystal fused dense corundum with large volume density and low apparent porosity is selected as the aggregate. In this example, the volume density of corundum is 2.79-2.81g/cm³The apparent porosity of corundum is 2-4.5%. The large-crystal fused compact corundum has stable chemical properties and good slag resistance, so that the separator prefabricated part 10 has good slag resistance.

Second, silicon carbide (SiC): high purity silicon carbide is preferably selected to improve the slag erosion resistance, wear resistance (i.e., molten iron erosion resistance), and thermal shock resistance of the refractory material by virtue of its high melting point, stable chemistry, and high hardness.

Thirdly, carbon materials: the carbon material mainly comprises C, and preferably adopts high-temperature asphalt subjected to high-temperature modification treatment, so that the slag resistance and the thermal shock stability of the refractory material are improved.

Fourthly, ultra-fine powder: the superfine powder with different granularities and different varieties is added, and the characteristics of the superfine powder are utilized to improve the fluidity of the refractory material during molding, improve the workability, reduce the porosity of the refractory material and increase the volume density to ensure the densification of the material; meanwhile, the sintering performance of various superfine powders at different temperatures is utilized, the medium-temperature and high-temperature sintering strength of the refractory material is improved, the absolute value difference of the medium-temperature and high-temperature strength of the refractory material is reduced, the thermal shock stability of the refractory material is improved, and the stripping and cracking of the refractory material are reduced. In this embodiment, the ultrafine powder is a mixture of silicon dioxide and clay powder, or a mixture of silicon oxide powder and clay powder, and the particle size of the ultrafine powder is not greater than 5 um.

Proper amount of non-oxide is added to raise the antioxidant performance of the refractory material.

Fifthly, antioxidant: preferably, the synthetic antioxidant of oxide-non-oxide is selected to improve the oxidation resistance of the refractory. In this example, the antioxidant is silicon carbide.

Sixthly, water: tap water having a pH of 6.6 to 7.5 is preferably selected.

Further, there are two preferred embodiments of the refractory material of the separator preform 10 in the present application as follows.

The first embodiment is as follows: 73.6% by mass of corundum, 10.5% by mass of silicon carbide, 3.2% by mass of high-temperature asphalt, 6.4% by mass of a mixture of silica and clay powder, 1.1% by mass of silicon carbide, and 5.2% by mass of water.

Example two: 73.6% by mass of corundum, 10.5% by mass of silicon carbide, 3.2% by mass of high-temperature asphalt, 6.4% by mass of a mixture of silicon oxide powder and clay powder, 1.1% by mass of silicon carbide, and 5.2% by mass of water.

Further, in the step S1, when the raw material components of the separator preform 10 are kneaded, it is preferable to knead the raw material components in a forced mixer. And firstly, pouring aggregates (namely corundum, silicon carbide and carbon materials) with different grain diameters, mixing for 1 minute, then adding the mixed fine powder (namely superfine powder and antioxidant), mixing for 2-3 minutes, then adding tap water with the pH value of 6.6-7.5, stirring for 3 minutes, and finishing mixing.

Further, in the step S2, the prefabricated template is vibrated by the eccentric vibrator to form the mixed material; and after the casting material on the template is molded, the surface of the casting material is coated, the casting material can be demoulded after curing for 22-30 hours, preferably 24 hours, the casting material is cured for 3 days at normal temperature after demould, the blank is not drenched or exposed to the sun during curing, and then the next baking and firing process can be carried out.

Further, in step S3, the temperature change in the tunnel kiln is strictly controlled during the baking and firing of the blank to ensure that the blank does not crack during the baking and firing process at low, medium, and high temperatures, thereby preventing the quality of the fired separator preform 10 from being affected. In the view shown in fig. 4, the temperature rise from 0 ℃ to 1000 ℃ within 0-20 hours is the first temperature rise stage and is linearly changed, the temperature rise is fast, and the temperature rise rate is large; the temperature rise from 1000 ℃ to 1480 ℃ within 20-50 hours is a second temperature rise stage and is linearly changed, the temperature rise is slow, and the temperature rise rate is low; keeping the temperature at 1480 ℃ within 50-70 hours to form a constant temperature stage and a heat preservation area, wherein the temperature in the stage is basically kept unchanged and is kept at about 1480 ℃; the temperature is reduced from 1480 ℃ to 0 ℃ within 70-120 hours, which is a cooling stage and is linearly changed.

In addition, the kiln of the tunnel kiln adopts a firepower thermal radiation type closed furnace body structure design, so that the blank can be uniformly heated in two heat transfer environments of thermal radiation and hot gas convection; in addition, an automatic electric control system of the kiln adopts a singlechip to control a contactless silicon controlled rectifier, so that accurate, stable and reliable data guarantee can be achieved no matter the temperature is raised or kept constant. In the baking and firing process of the separator prefabricated part 10, the cooling link adopts a natural cooling and non-kiln-opening mode, so that cracks formed due to thermal stress of the internal structure of the separator prefabricated part 10 caused by too fast cooling are avoided, and the baking quality of the separator prefabricated part 10 is ensured.

In summary, the physicochemical indexes of the main channel iron slag separator obtained by the manufacturing process are shown in the following table 1.

TABLE 1 physicochemical indices of main channel iron and slag separator

In table 1 above, 110℃ × 24h means that the separator preform 10 is heat-treated in a temperature environment of 110 ℃ for 10 hours, and 1450℃ × 3h means that the separator preform 10 is heat-treated in a temperature environment of 1450 ℃ for 3 hours.

Therefore, the main runner slag-iron separator has the characteristics of high strength, good slag resistance, molten iron erosion resistance, high thermal shock stability and good oxidation resistance, and further has a long service life, the slag-passing repairing operation caused by cracking or excessive melting loss cannot occur in the using process, the slag-passing problem caused by cracking and excessive melting loss in the prior art is thoroughly solved, the passive situation of midway repairing is avoided, the service life of the integrated main runner slag-iron separator is synchronous with the high-iron flux of the main runner 20, and the integrated main runner slag-iron separator has a very good practical application value.

In conclusion, the present invention effectively overcomes various disadvantages of the prior art and has high industrial utilization value.

The foregoing embodiments are merely illustrative of the principles and utilities of the present invention and are not intended to limit the invention. Any person skilled in the art can modify or change the above-mentioned embodiments without departing from the spirit and scope of the present invention. Accordingly, it is intended that all equivalent modifications or changes which can be made by those skilled in the art without departing from the spirit and technical spirit of the present invention be covered by the claims of the present invention.