阅读说明：本技术 一种出钢口填料及填充方法 (Steel tapping hole filler and filling method ) 是由 周旺枝 张洪雷 刘黎 刘孟 邹龙 徐国涛 刘婳 于 2020-06-30 设计创作，主要内容包括：本发明公开了一种出钢口填料及填充方法,所述出钢口填料,由上下两层构成,上层原料为石英砂、烧结镁砂,镁橄榄石砂,镁硅砂,废镁砖,辅料为增碳剂和助烧剂；下层为白云石砂；使用时,按配比、粒度级配称取上层原料,先将主要原料在混料机中混合15～30min后,然后向混料机中加入辅料,继续混合20～30min后进行装包或施工使用。本发明所述出钢口填料及填充方法克服了现有出钢口填料流动性差、自开率低、难烧结等局限性,满足出钢工艺要求。(The invention discloses a steel-tapping hole filler and a filling method, wherein the steel-tapping hole filler consists of an upper layer and a lower layer, the upper layer is made of quartz sand, sintered magnesia, forsterite sand, magnesia silica sand and waste magnesia brick as raw materials, and the auxiliary materials are a carburant and a sintering aid; the lower layer is dolomite sand; when the material is used, the upper-layer raw materials are weighed according to the proportion and the particle size distribution, the main raw materials are mixed in a mixer for 15-30 min, then the auxiliary materials are added into the mixer, and the mixture is continuously mixed for 20-30 min and then packaged or constructed for use. The steel tapping hole filler and the filling method overcome the limitations of poor fluidity, low self-opening rate, difficult sintering and the like of the existing steel tapping hole filler, and meet the steel tapping process requirements.)

1. A tap hole filler is characterized in that: the steel tapping hole filler consists of an upper layer and a lower layer, wherein the upper layer is made of quartz sand, sintered magnesia, forsterite sand, magnesia silica sand and waste magnesia bricks, and the auxiliary materials are a carburant and a sintering aid; the lower layer is dolomite sand.

2. The tap-hole filler according to claim 1, characterized in that: the upper layer comprises the following raw materials in percentage by mass: 25-45% of quartz sand, 30-60% of sintered magnesia, and forsterite sand: 10-35%, magnesia silica sand: 5-20%, waste magnesium brick: 1-20%, carburant: 0-2% of a sintering aid and 1-12% of a sintering aid.

3. The tap-hole filler according to claim 2, characterized in that: the recarburizing agent is selected from one or a mixture of several of graphite powder, coke powder or asphalt powder according to any proportion.

4. The tap-hole filler according to claim 2, characterized in that: the sintering aid is one or a mixture of boric acid, iron ore powder and bentonite according to a proportion; preferably, the sintering aid comprises the following components in percentage by mass: 0.5-25% of boric acid, 3-30% of bentonite and 40-80% of iron ore powder.

5. The tap-hole filler according to claim 2, characterized in that: the quartz sand comprises the following components in percentage by mass: 50-70% of 1-3 mm, 1-5% of 0-0.5 mm and 25-45% of 0.5-1 mm; the sintered magnesia comprises the following components in percentage by mass: 55-75% of 1-3 mm; 20-40% of 0.074-1 mm; 0-0.074 mm 5-15%; the forsterite sand comprises the following components in percentage by mass: 51-73% of 1-4 mm; 18-37% of 0.074-1 mm; 0-0.074 mm 3-16%.

6. The tap-hole filler according to claim 2, characterized in that: sorting the waste magnesium bricks, removing impurities, and crushing according to the granularity requirement; the waste magnesia brick comprises the following components in percentage by mass: 50-75% of 1-3 mm, and 25-55% of 0-1 mm; the magnesium-silica sand comprises the following components in percentage by mass: 49-74% of 1-3 mm and 25-50% of 0-1 mm; the particle size of the sintering aid is less than 0.074 mm; the grain size of the carburant is less than 0.074 mm.

7. The tap-hole filler according to claim 2, characterized in that: the dolomite sand comprises the following components in percentage by mass: 48-74% of 1-3 mm; 15-62% of 0.5-1 mm.

8. The tap-hole filler according to claim 1, characterized in that: the lower layer of the steel tapping hole filler accounts for 1/5-1/3 of the total filler volume.

9. The method for preparing a top raw material for a tap-hole filler according to any one of claims 1 to 8, comprising the steps of: weighing the upper-layer raw materials according to the proportion and the particle size distribution, mixing the main raw materials in a mixer for 15-30 min, adding the auxiliary materials into the mixer, continuously mixing for 20-30 min, and then packaging or constructing for use.

10. Method for filling a tap-hole filler according to any one of claims 1 to 8, characterised in that it comprises the following steps: the method comprises the steps of firstly filling dolomite sand with the volume of 1/3-1/5 of the steel-tapping hole at the bottom of the steel-tapping hole of the electric furnace, and then filling upper-layer filler on the dolomite sand to fill the whole steel-tapping hole.

Technical Field

The invention relates to a steel tapping hole filler, belonging to the field of refractory materials for industrial kilns.

Background

The tap hole filler is one of key varieties of refractory materials for smelting molten steel in a metallurgical kiln, and the self-opening rate of the tap hole filler is important for ensuring a normal smelting period. On one hand, the steel has to have proper sintering performance so as to form a sintering layer, so that the high-temperature molten steel is prevented from leaking to the lower part of a steel outlet, and accidents caused by floating of the filler are prevented; on the other hand, the thickness of the sintered layer formed by the sintered layer is required to be moderate, so that when the baffle at the lower part of the steel tapping hole is opened, the filler falls under the action of self gravity, and the sintered layer is cracked and broken under the action of hydrostatic pressure and thermal stress after cold air is sucked in to form self-flow. However, the tap hole filler on the market at present has the problems of poor fluidity, low self-opening rate and the like, and influences on molten steel smelting. The patent CN201110363848.7 is mainly produced by taking forsterite sand, magnesia-calcium sand and magnesia-silica sand as main raw materials and adding a boric acid composite sintering agent, has the characteristics of impermeability of molten steel, high refractoriness and the like, but cannot ensure the casting rate. The patent CN201910456778.6 takes quartz sand, olivine, magnesia and chromite as main raw materials, 3 different EBT steel-tapping hole fillers can be prepared by combining different raw materials and adding different composite sintering agents and reducing agents, the self-opening rate of the EBT steel-tapping hole fillers can reach more than 96 percent, and the EBT steel-tapping hole fillers containing chromite have higher self-opening rate which can reach more than 98 percent. However, the raw materials of the invention adopt chromite, and chromium in the chromite is not beneficial to environmental protection. Therefore, it is very important to develop the steel tapping hole filler with proper sintering performance, good fluidity, environmental protection, high self-opening rate and the like.

Disclosure of Invention

Based on the defects of the prior art, the technical problem to be solved by the invention is to provide the steel-tapping hole filler with good treatment effect and the filling method, and the steel-tapping hole filler and the filling method overcome the limitations of poor fluidity, low self-opening rate, difficult sintering and the like of the existing steel-tapping hole filler and meet the steel-tapping process requirements.

In order to solve the technical problems, the invention provides a steel-tapping hole filler which comprises an upper layer and a lower layer, wherein the upper layer is made of quartz sand, sintered magnesia, forsterite sand, magnesia silica sand and waste magnesia bricks, and auxiliary materials are a carburant and a sintering aid; the lower layer is dolomite sand.

Preferably, the tap-hole filler provided by the invention further comprises part or all of the following technical characteristics:

as an improvement of the technical scheme, the upper layer raw material comprises the following components in percentage by mass: 25-45% of quartz sand, 30-60% of sintered magnesia, and forsterite sand: 10-35%, magnesia silica sand: 5-20%, waste magnesium brick: 1-20%, carburant: 0-2% of a sintering aid and 1-12% of a sintering aid.

As an improvement of the technical scheme, the carburant is selected from one or a mixture of several of graphite powder, coke powder and asphalt powder according to any proportion.

As an improvement of the technical scheme, the sintering aid is one or a mixture of boric acid, iron ore powder and bentonite according to a proportion; preferably, the sintering aid comprises the following components in percentage by mass: 0.5-25% of boric acid, 3-30% of bentonite and 40-80% of iron ore powder.

As an improvement of the technical scheme, the quartz sand comprises the following components in percentage by mass: 50-70% of 1-3 mm, 1-5% of 0-0.5 mm and 25-45% of 0.5-1 mm; the sintered magnesia comprises the following components in percentage by mass: 55-75% of 1-3 mm; 20-40% of 0.074-1 mm; 5-15% with the thickness of 0-0.074 mm; the forsterite sand comprises the following components in percentage by mass: 51-73% of 1-4 mm; 18-37% of 0.074-1 mm; 0-0.074 mm 3-16%.

As an improvement of the technical scheme, the waste magnesium bricks are sorted, impurities are removed, and the waste magnesium bricks are crushed according to the requirement of particle size; the waste magnesia brick comprises the following components in percentage by mass: 50-75% of 1-3 mm, and 25-55% of 0-1 mm; the magnesium-silica sand comprises the following components in percentage by mass: 49-74% of 1-3 mm and 25-50% of 0-1 mm; the particle size of the sintering aid is less than 0.074 mm; the grain size of the carburant is less than 0.074 mm.

As an improvement of the technical scheme, the dolomite sand comprises the following components in percentage by mass: 48-74% of 1-3 mm; 15-62% of 0.5-1 mm.

As an improvement of the technical scheme, the lower-layer filler of the steel-tapping hole filler accounts for 1/5-1/3 of the total filler volume.

The method for preparing the upper layer raw material of the steel-tapping hole filler comprises the following steps: weighing the upper-layer raw materials according to the proportion and the particle size distribution, mixing the main raw materials in a mixer for 15-30 min, adding the auxiliary materials into the mixer, continuously mixing for 20-30 min, and then packaging or constructing for use.

The method for filling a tap-hole filler as set forth in any one of the above claims, comprising the steps of: the method comprises the steps of firstly filling dolomite sand with the volume of 1/3-1/5 of the steel-tapping hole at the bottom of the steel-tapping hole of the electric furnace, and then filling upper-layer filler on the dolomite sand to fill the whole steel-tapping hole.

Compared with the prior art, the technical scheme of the invention has the following beneficial effects: (1) according to the invention, the main raw materials and the auxiliary materials are compounded to improve the fluidity, the sintering property and the casting rate of the filler, so that the defects of poor fluidity, difficult sintering of the upper layer, low self-opening rate and the like of the existing steel tapping hole filler are overcome, the process requirement of steel tapping is met, and the cost is low.

(2) The quartz sand, the magnesia, the forsterite sand and the like in the main raw materials have high refractoriness and molten steel erosion resistance, boric acid in the sintering aid and iron compounds in iron ore powder easily react with the sintering agent rapidly, and the volume of the boric acid and the iron compounds expands to form a thin porous sintering layer which is easy to cast under the pressure of molten steel; meanwhile, the carburant is beneficial to improving the lubricating property and the heat conductivity among filler particles.

(3) The invention has two layers of fillers, the upper layer of filler has high refractoriness and proper sintering property, the formed sintering layer has moderate thickness, the lower layer of dolomite sand is used as a part of the filler, and the dolomite sand is changed into slag after tapping, thereby realizing double functions.

The foregoing description is only an overview of the technical solutions of the present invention, and in order to make the technical means of the present invention more clearly understood, the present invention may be implemented in accordance with the contents of the description, and in order to make the above and other objects, features, and advantages of the present invention more clearly understood, the following detailed description is given in conjunction with the preferred embodiments.

Detailed Description

Other aspects, features and advantages of the present invention will become apparent from the following detailed description, which, when taken in conjunction with the drawings, illustrate by way of example the principles of the invention.