阅读说明：本技术 一种用于顶燃式热风炉炉顶的耐热震中重质耐火材料及制备方法 (Heavy refractory material used for top combustion type hot blast stove top and capable of resisting thermal shock and preparation method thereof ) 是由 董红芹 樊效乐 李建涛 于 2020-05-25 设计创作，主要内容包括：本发明涉及一种用于顶燃式热风炉炉顶的耐热震中重质耐火材料,以微孔轻质球形骨料做关键原料制备出体密度较低的耐火材料,既能满足顶燃式热风炉对抗热震稳定性能要求,同时有效降低了炉体容重和炉顶壁面导热率,使顶燃式热风炉能够长期稳定节能运行。本发明还涉及一种制备上述中重质耐火材料的制备方法。(The invention relates to a heavy refractory material for resisting thermal shock of a top combustion type hot blast stove top, which is a refractory material with lower bulk density prepared by taking microporous light spherical aggregate as a key raw material, can meet the requirement of the top combustion type hot blast stove on thermal shock resistance stability, and effectively reduces the volume weight of a stove body and the wall surface thermal conductivity of the top combustion type hot blast stove top, so that the top combustion type hot blast stove can stably run in an energy-saving manner for a long time. The invention also relates to a preparation method for preparing the medium-heavy refractory material.)

1. The heavy refractory material for the top combustion type hot blast stove top is characterized by comprising a microporous light spherical aggregate component, a heavy refractory aggregate component, a fine powder alumina component and a binding agent component which are 100% in total mass, wherein the mass ratio of the microporous light spherical aggregate component in the refractory material is more than or equal to 10%.

2. The refractory of claim 1, wherein the microporous lightweight spherical aggregate component comprises a microporous lightweight spherical mullite aggregate having a particle size specification of 0.3 mm to 1 mm.

3. The refractory of claim 2, wherein the microporous lightweight spherical mullite aggregate is Al₂O₃The content is more than or equal to 68 percent and the bulk density is less than or equal to 1.5g/cm³The aggregate of (1).

4. The refractory of claim 1 or claim 2, wherein the heavy refractory aggregate component comprises any one or a combination of any more of andalusite having a particle size specification of 1mm to 3mm, andalusite having a particle size specification of 0.088mm or less, kyanite having a particle size specification of 150 mesh or more, mullite having a particle size specification of 1mm to 3mm, and cordierite having a particle size specification of 0.088mm or less.

5. The refractory of claim 4, wherein the Al of the andalusite is₂O₃The content is more than or equal to 55 percent; al of the kyanite₂O₃The content is more than or equal to 53 percent; al of the cordierite₂O₃The content ranges from 33% to 35%, and the cordierite has an MgO content ranging from 13% to 15%.

6. The refractory according to claim 1 or 2, wherein the fine alumina component comprises any one or a combination of any more of alumina fine powder, white corundum powder and tabular corundum powder having a particle size of 5 μm or less, and the mass ratio of the fine alumina component in the refractory is 10% or less.

7. The refractory according to claim 6, wherein Al of the fine alumina powder, the white corundum powder and the plate-like corundum powder₂O₃Content (wt.)Greater than or equal to 99 percent.

8. The refractory of claim 1 or claim 2, wherein the binder component comprises suzhou clay having a particle size of 150 mesh or greater, and wherein the binder component is present in the refractory at 10% by mass or less.

9. A preparation method of a heavy refractory material used for the top of a top combustion type hot blast stove and resistant to thermal shocks is characterized by comprising the following steps:

s1, mixing the microporous lightweight spherical aggregate component, the heavy refractory aggregate component, the fine powder alumina component and the binder component, adding paper pulp which accounts for 8% of the total mass of the microporous lightweight spherical aggregate component, the heavy refractory aggregate component, the fine powder alumina component and the binder component, and stirring for 5-20 minutes by using a stirrer to form fully and uniformly mixed pug;

s2, lightly pressing the pug by using a hydraulic press to reduce the thickness of the pug to the point that the single weight of the pug is equal to the bulk density range of 2.0-2.1 g/cm³Obtaining a semi-finished product blank body corresponding to the single weight;

and S3, placing the semi-finished blank in a constant temperature furnace at 1380 ℃ to be fired for 6 to 16 hours to obtain a finished refractory material.

10. The method of claim 9, wherein the pulp is a pulp having a specific gravity of 1.2.

Technical Field

The invention relates to the technical field of novel material preparation, in particular to a heavy refractory material used for resisting thermal shock of a top combustion type hot blast stove top and a preparation method thereof.

Background

The upper part of the structure of the top-burning hot blast stove is a premixing chamber part of a burner, the working temperature generally fluctuates up and down within the range of 450 to 1000 ℃, and the main function is that air and coal gas are mixed and then are further burnt in a lower combustion chamber. The top of the premixing chamber is positioned at the top end of the furnace, the height is about 3m generally, the temperature fluctuation of the position is large, the load is low, and the requirement on the thermal shock resistance stability of the refractory material is high.

Disclosure of Invention

In order to solve the defects of the prior art, the invention provides a heavy refractory material with low bulk density for resisting thermal shock for the top combustion type hot blast stove top and a preparation method thereof.

In order to achieve the above purpose, the technical scheme adopted by the invention comprises the following steps:

a thermal shock resistant heavy refractory material for use in the roof of a top-fired hot blast stove, characterised in that the composition of the refractory material comprises a microporous lightweight spherical aggregate component, a heavy refractory aggregate component, a fine powder alumina component and a binder component in a combined mass proportion of 100%, and the mass proportion of the microporous lightweight spherical aggregate component in the refractory material is 10% or more, in particular it may be preferred that the mass proportion in the refractory material is more than 20%.

Further, the microporous lightweight spherical aggregate component comprises microporous lightweight spherical mullite aggregate with the particle size specification of 0.3 mm to 1 mm.

Further, the microporous lightweight spherical mullite aggregate is Al₂O₃The content is more than or equal to 68 percent and the bulk density is less than or equal to 1.5g/cm³The aggregate of (1).

Further, the heavy refractory aggregate component comprises any one or a combination of any more of andalusite with a grain size specification of 1mm to 3mm, andalusite with a grain size specification of 0.088mm or less, kyanite with a grain size specification of 150 meshes or more, mullite with a grain size specification of 1mm to 3mm, and cordierite with a grain size specification of 0.088mm or less.

Further, Al of said andalusite₂O₃The content is more than or equal to 55 percent; al of the kyanite₂O₃The content is more than or equal to 53 percent; al of the cordierite₂O₃The content ranges from 33% to 35%, and the cordierite has an MgO content ranging from 13% to 15%.

Further, the fine powder alumina component comprises any one or combination of any more of alumina micro powder, white corundum powder and tabular corundum powder with the particle size specification of less than or equal to 5 microns, and other fine powder materials with high alumina content and suitable particle size specifications can be selected as the fine powder alumina component, and the mass ratio of the fine powder alumina component in the refractory material is less than or equal to 10%.

Further, Al of the alumina micropowder, the white corundum powder and the plate-shaped corundum powder₂O₃The content is more than or equal to 99 percent.

Further, the binder component comprises Suzhou soil with a particle size specification of more than or equal to 150 meshes, and the mass ratio of the binder component in the refractory material is less than or equal to 10%.

The invention also comprises a preparation method of the heavy refractory material for preparing the top combustion type hot blast stove top, which is characterized by comprising the following steps:

s1, mixing the microporous lightweight spherical aggregate component, the heavy refractory aggregate component, the fine powder alumina component and the binder component, adding paper pulp which accounts for 8% of the total mass of the microporous lightweight spherical aggregate component, the heavy refractory aggregate component, the fine powder alumina component and the binder component, and stirring for 5-20 minutes by using a stirrer to form fully and uniformly mixed pug;

s2, lightly pressing the pug by using a hydraulic press to reduce the thickness of the pug to the point that the single weight of the pug is equal to the bulk density range of 2.0-2.1 g/cm³Obtaining a semi-finished product blank body corresponding to the single weight;

and S3, placing the semi-finished blank in a constant temperature furnace at 1380 ℃ to be fired for 6 to 16 hours to obtain a finished refractory material.

Further, the pulp is a pulp of a specific gravity of 1.2.

The invention has the beneficial effects that:

by adopting the thermal shock resistant heavy refractory material for the top combustion type hot blast stove top, the density of the material body is reduced by adding the microporous light spherical aggregate component to be used as a furnace lining material of the top combustion type hot blast stove top, the volume weight of the stove body can be obviously reduced, the heat conductivity coefficient of the wall surface of the stove body is reduced, and the overflow of heat in the stove is reduced, so that the fuel consumption of the hot blast stove is reduced, and the purpose of saving energy is achieved; the reduction of heat overflow in the furnace is also beneficial to reducing the temperature of the outer layer of the furnace top, slowing down the heat loss of materials outside the furnace body and prolonging the service life of the hot blast furnace.

Detailed Description

For a clearer understanding of the contents of the present invention, reference will be made to the following examples.

The invention effectively reduces the bulk density of the furnace top material by adding the microporous lightweight spherical aggregate component with the mass ratio of not less than 10 percent on the basis of the original heavy refractory aggregate component, and simultaneously enhances the heat insulation performance of the whole furnace top by introducing the microporous material.

The medium-heavy refractory material is formed by mixing and pressing microporous light spherical aggregate components, heavy refractory aggregate components, fine powder alumina components and binding agent componentsThe refractory material obtained by the warm firing has an aluminum content of not less than 50%, a porosity of not more than 40%, and a bulk density in the range of 1.8-2.0g/cm³The refractoriness under load is about 1400 ℃, the thermal shock resistance is not less than 50 times, and the thermal conductivity range of 350 ℃ is 0.9-1.5 w/m.k.

The invention also comprises a preparation method for preparing the heavy refractory material, which preferably comprises the following steps:

s1, mixing the microporous lightweight spherical aggregate component, the heavy refractory aggregate component, the fine powder alumina component and the binder component according to a set proportion, stirring for 10 minutes by using a planetary stirrer, and adding paper pulp with the specific gravity of 1.2 which is 8 percent of the total mass of the microporous lightweight spherical aggregate component, the heavy refractory aggregate component, the fine powder alumina component and the binder component in the stirring process to form fully and uniformly mixed pug;

s2, lightly pressing the pug by using a hydraulic press to reduce the thickness of the pug to a bulk density equal to 2.1g/cm³Obtaining a semi-finished product blank body corresponding to the single weight;

and S3, placing the semi-finished product blank in a constant temperature furnace at 1380 ℃ to be fired for 8 hours to obtain a finished product of the refractory material.

An exemplary embodiment of the invention is shown below: