A sol-coated slag remover and its preparation method and application

Abstract

The present invention relates to the technical field of ductile iron, specifically a sol-coated slag remover and its preparation method and application, the slag remover is prepared from a main material, an auxiliary material and a coating material, the main material is made of the following raw materials in weight percentage: perlite powder 75%-85%, expanded perlite powder 2%-10%, bentonite 3%-10%, silicon carbide powder 0.5%-2%, graphite powder 5%-10%, aluminum fluoride 0.1%-2%; the auxiliary materials are potassium humate and water, the amount of potassium humate is 0.5-5% of the main material, the amount of water is 18-25% of the main material; the amount of coating material is 1-5% of the main material. The slag remover of the present invention can prevent sticking balls and dust pollution, while increasing the foaming multiple, expanding the volume, improving the slag aggregation efficiency, improving the high-temperature viscosity of the foam, facilitating slag removal, and some components are heated at high temperature and have a deoxidation effect, ensuring the temperature of molten iron and the reducing atmosphere.

Description

Technical Field

[0001] The invention relates to the technical field of ductile iron, in particular to a sol-coated slag remover and a preparation method and application thereof. Background Art

[0002] The purpose of the slag remover is to remove the slag produced by spheroidization, inoculation, deoxidation, desulfurization and dephosphorization in the ductile iron process. The addition of the slag remover acts as a seed, prompting tiny slag to aggregate into large slag (foaming process). The slag rapidly foams so that it covers the surface of the molten iron and is easy to remove. Heat is generated during foaming, and at the same time, the foaming layer covers the surface of the molten metal, which plays a role in heat preservation, shielding and maintaining a reducing atmosphere.

[0003] The original cast iron slag remover used straw ash or asbestos ash, but the use of straw ash or asbestos ash can easily cause occupational diseases such as silicosis or skin allergies, so this technology has been gradually banned.

[0004] Existing ductile iron slag removal materials use partially dehydrated perlite or composite materials with partially dehydrated perlite as the main raw material, and fly ash is also used as a slag removal agent and thermal insulation covering agent. For example, the invention patent with application number 2012102673740 discloses a composite slag removal agent, the mass percentage of which is: perlite fine powder 79%-95%, active silicon dioxide 0.2%-10%, active aluminum oxide 0.1%-5% and water glass 2%-15%. This solution is prone to sticking problems when used in practice. For example, the article "Development of Fly Ash Covering Agent for Cast Iron" in "Foundry" No. 12, 1991 discloses a slag removal agent with fly ash, perlite and carbonate as foaming agents. This slag removal agent has carbonate decomposition and gas diffusion, which causes a large amount of heat loss, which has a certain impact on casting and casting quality.

[0005] Therefore, in order to solve the problems of particle pollution, sticking and large amount of heat loss in existing slag removers, a sol-coated slag remover and its preparation method and application are proposed. Summary of the invention

[0006] The object of the present invention is to provide a sol-coated slag remover and a preparation method and application thereof, so as to solve the problems raised in the above background technology.

[0007] To achieve the above object, the present invention provides the following technical solution: a sol-coated slag remover, prepared from a main material, an auxiliary material and a coating material, wherein the main material is made of the following raw materials in percentage by weight: perlite powder 75%-85%, expanded perlite powder 2%-10%, bentonite 3%-10%, silicon carbide powder 0.5%-2%, graphite powder 5%-10%, and aluminum fluoride 0.1%-2%;

[0008] The auxiliary materials are potassium humate and water, the amount of potassium humate is 0.5-5% of the main material, and the amount of water is 18-25% of the main material;

[0009] The amount of the coating material is 1-5% of the main material.

[0010] Furthermore, the coating material is aluminum phosphate sol or aluminum sol.

[0011] Furthermore, the volume density of the aluminum phosphate sol is 1.47t / m 3 , pH value is 2.5, aluminum oxide content is 43%, and phosphorus pentoxide content is 42%.

[0012] Furthermore, the volume density of the aluminum sol is, the pH value is 4.0, and the solid content is 20%.

[0013] Furthermore, the slag remover is in the shape of a rod, with a diameter of 4mm-6mm, a length of 5mm-10mm, a compressive strength greater than 1MPa, a flexural strength greater than 1.2MPa, and a bulk density of 0.8t / m 3 -1.4t / m 3 , the foaming temperature is 1120℃-1150℃.

[0014] The preparation method of the above-mentioned sol-coated slag remover comprises:

[0015] S1 ingredients: weigh the above raw materials according to weight percentage, slowly add potassium humate into water in equal amounts, and stir evenly to prepare a potassium humate solution;

[0016] S2 Mixing: Mix the perlite powder, expanded perlite powder, bentonite, silicon carbide powder, graphite powder and aluminum fluoride evenly, add them into the potassium humate solution, and mix them into a slag remover slurry;

[0017] S3 molding: After the mixed deslagging agent mud is sealed and aged for 24 hours, it is put into an extrusion molding machine to extrude into deslagging agent mud strips with a diameter of 4mm-6mm. The deslagging agent mud strips are cut into deslagging agent mud strip segments with a length of 5mm-10mm by a wire cutting machine;

[0018] S4 drying: the slag remover mud strips are dried in a mesh belt roller kiln at a temperature of 150°C for 60-120 minutes. After drying, the moisture content is less than 1%.

[0019] S5 Gluing: The dried slag remover mud strips pass through the coating material curtain glue coating device via a mesh belt, and the coating material will be evenly coated on the outer periphery of the mud strips to form a coating layer;

[0020] S6 low-temperature sintering: The slag remover strips coated with the coating material are sintered at low temperature in a mesh belt roller kiln, the sintering temperature is 350°C-450°C, the sintering time is 25-50 minutes, and the sintering agent is obtained.

[0021] Furthermore, the coating layer applied in S5 has a thickness of 1 mm.

[0022] The application of the above sol-coated slag remover in ductile iron is as follows:

[0023] During spheroidization, it is placed in the dam bag together with the spheroidizing agent and inoculant. After the molten iron is poured in, a heat-insulating cover is added. During the spheroidization reaction, the slag remover quickly floats, foams, generates heat, and gathers slag, thus playing the role of slag removal and covering heat preservation.

[0024] Before subcontracting, the slag remover is put on the surface of molten iron. After meeting the molten iron, the slag remover quickly foams, generates heat, and gathers slag, playing the role of slag removal and covering and heat preservation;

[0025] After transfer, sprinkle a certain amount of slag remover on the molten iron in the casting ladle, which will quickly foam, generate heat, and gather slag, thus playing the role of slag removal and covering insulation.

[0026] Compared with the prior art, the present invention has the following beneficial effects:

[0027] The main material components include 75%-85% perlite powder, 2%-10% expanded perlite powder, 3%-10% bentonite, 0.5%-2% silicon carbide powder, 5%-10% graphite powder, and 0.1%-2% aluminum fluoride. The content of perlite powder in the perlite industrial solid waste is as high as 78%-95%. The present invention turns waste into treasure, not only solves the problem of environmental pollution, but also realizes efficient utilization of resources in the perlite processing industry.

[0028] In the preparation method, the potassium humate solution in the auxiliary material interacts with the bentonite component in the main material to play a bonding and plasticizing role, especially the bentonite moistened with the potassium humate solution plays a highly efficient bonding role, which can significantly improve the wet strength, dry strength and sintering strength of the mud strips;

[0029] In the formula, potassium humate, graphite powder and silicon carbide not only play the role of carbon increase and deoxidation, but also act as foaming agents; silicon carbide is the main foaming agent, and the foaming pore size can reach micron level and be evenly distributed; during the foaming and deoxidation process of the cast iron process, potassium humate, graphite powder and silicon carbide can also release heat to ensure the working temperature of the molten iron in the spheroidizing ladle and the casting ladle.

[0030] The coating layer is aluminum phosphate sol or aluminum sol, which can form a high-strength flexible shell on the surface of the slag remover, improve the strength and drop resistance of the slag remover rod, and the material is acidic high-temperature refractory material, which can quickly gather acidic slag and prevent ball sticking. In addition, it also has the effect of increasing the viscosity of the slag melt and improving the slag removal efficiency.

[0031] The rod-shaped material and its high-strength flexible shell can reduce dust pollution. The aluminum fluoride in the component can wet the shell at high temperature to improve the adsorption of slag. Another function of wetting is to prevent the gas in the foam of the slag remover from breaking out of the shell, reduce the buoyancy of the slag and reduce the temperature of the slag and molten iron. The molten iron that has been cooled by spheroidization can quickly form high-viscosity slag, which is convenient for rapid slag aggregation and quick slag removal. DETAILED DESCRIPTION

[0032] The following will be combined with specific embodiments to clearly and completely describe the technical solutions 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. 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. Example

[0033] A sol-coated slag remover is prepared from a main material, an auxiliary material and a coating material.

[0034] The main material is made of the following raw materials in percentage by weight: 78% perlite powder, 5% expanded perlite powder, 7% bentonite, 1% silicon carbide powder, 8% graphite powder, and 1% aluminum fluoride;

[0035] The auxiliary materials are potassium humate and water. The amount of potassium humate is 1% of the main material, and the amount of water is 20% of the main material.

[0036] The coating material is aluminum phosphate sol. The volume density of aluminum phosphate sol is 1.47t / m 3 , pH value is 2.5, aluminum oxide content is 43%, and phosphorus pentoxide content is 42%.

[0037] The preparation method of the above-mentioned sol-coated slag remover comprises:

[0038] S1 ingredients: weigh the above raw materials by mass percentage, the total weight of the main material is 500 kg, potassium humate is 5 kg, water is 100 kg, potassium humate is added with water and stirred evenly to prepare potassium humate solution;

[0039] S2 Mixing: Mix the perlite powder, expanded perlite powder, bentonite, silicon carbide powder, graphite powder and aluminum fluoride evenly, add the potassium humate solution into the mixing process, mix into a slag remover mud for later use;

[0040] S3 molding: After the mixed deslagging agent mud is sealed and aged for 24 hours, it is put into an extrusion molding machine to extrude into deslagging agent mud strips with a diameter of 5 mm. The deslagging agent mud strips are cut into 10 mm long deslagging agent mud strip segments by a wire cutting machine;

[0041] S4 drying: the slag remover mud strips are dried in a mesh belt roller kiln at a temperature of 150°C for 60 minutes. After drying, the moisture content is less than 1%.

[0042] S5 Glue coating: The dried slag remover mud strips are passed through the coating material curtain glue coating device via a mesh belt, and the sol of the coating material is evenly coated on the outer periphery of the mud strips to form a coating layer with a thickness of 1 mm;

[0043] S6 low-temperature sintering: The slag remover strips coated with the coating material are sintered at low temperature in a mesh belt roller kiln. The sintering temperature is 350°C and the sintering time is 30 minutes. During the sintering, part of the bound water is removed from the perlite powder, and the aluminum phosphate sol is dehydrated and more tightly combined with the slag remover strips to obtain a slag remover.

[0044] The specifications of the slag remover in this embodiment are: rod-shaped, diameter 5mm±1mm, length 10mm±1mm, compressive strength 2.5MPa, flexural strength 3.2MPa, volume density 0.86t / m 3 , initial foaming temperature: 1105℃. 1150℃ for 10min, bulk density 0.23t / m 3 The weight ratio of the coating material is about 2%.

[0045] The deslagging agent in this embodiment has the following application performance tests:

[0046] In the production of QT450-10 material rail iron plate castings in a 2-ton medium frequency electric furnace, its specific applications include:

[0047] 1) During spheroidization, the slag remover is placed in the dam bag together with the spheroidizing agent and inoculant. After the molten iron is poured in, an insulation cover is added. During the spheroidization reaction, the slag remover quickly floats, foams, generates heat, and aggregates slag, which plays the role of slag removal and covering insulation. The dosage is 8Kg / 2t molten steel. Spheroidization, slag aggregation, and slag removal are completed within 2 minutes.

[0048] 2) Before subcontracting, the slag remover is put into the surface of molten iron. After meeting the molten iron, the slag remover will quickly foam, generate heat, and gather slag, thus playing the role of slag removal and covering and heat preservation. The dosage is 2Kg / 2t molten steel, and slag gathering and slag removal can be completed within 2 seconds.

[0049] 3) After the transfer, sprinkle a certain amount of slag remover on the molten iron in the casting ladle, which will quickly foam, heat up, and gather slag, thus playing the role of slag removal and covering insulation. The molten iron in the casting ladle is 200 kg, and the dosage for each ladle is 100g, totaling 1kg. Inoculation, slag gathering, and slag removal can be completed within 2 seconds.

[0050] Compared with traditional slag removers, the dosage is reduced by 50%, the slag removal rate is increased by 30%, and the casting quality qualification rate is increased from 75% to 98.5%. Example

[0051] A sol-coated slag remover is prepared from a main material, an auxiliary material and a coating material.

[0052] The main material is made of the following raw materials in percentage by weight: 80% perlite powder, 4% expanded perlite powder, 6% bentonite, 0.5% silicon carbide powder, 8% graphite powder, and 1.5% aluminum fluoride;

[0053] The auxiliary materials are potassium humate and water. The amount of potassium humate is 1.2% of the main material, and the amount of water is 20% of the main material.

[0054] The coating material is aluminum phosphate sol. The volume density of aluminum phosphate sol is 1.47t / m 3 , pH value is 2.5, aluminum oxide content is 43%, and phosphorus pentoxide content is 42%.

[0055] The preparation method of the above-mentioned sol-coated slag remover comprises:

[0056] S1 Ingredients: Weigh the above raw materials by mass percentage, the total weight of the main material is 500 kg, potassium humate is 6 kg, and water is 100 kg. Slowly add potassium humate into water in equal amounts and stir evenly to prepare a potassium humate solution;

[0057] S2 Mixing: Mix the perlite powder, expanded perlite powder, bentonite, silicon carbide powder, graphite powder and aluminum fluoride evenly, add the potassium humate solution into the mixing process, mix into a slag remover mud for later use;

[0058] S3 molding: After the mixed deslagging agent mud is sealed and aged for 24 hours, it is put into an extrusion molding machine to extrude into deslagging agent mud strips with a diameter of 5 mm. The deslagging agent mud strips are cut into 10 mm long deslagging agent mud strip segments by a wire cutting machine;

[0059] S4 drying: the slag remover mud strips are dried in a mesh belt roller kiln at a temperature of 150°C for 60 minutes. After drying, the moisture content is less than 1%.

[0060] S5 Glue coating: The dried slag remover mud strips are passed through the coating material curtain glue coating device via a mesh belt, and the sol of the coating material is evenly coated on the outer periphery of the mud strips to form a coating layer with a thickness of 1 mm;

[0061] S6 low-temperature sintering: The slag remover strip segments coated with the glaze slurry of the coating material are sintered at low temperature in a mesh belt roller kiln. The sintering temperature is 350°C and the sintering time is 40 minutes. During the sintering, part of the bound water is removed from the perlite micropowder, and the aluminum phosphate sol is dehydrated and more tightly combined with the slag remover strip segments to obtain the slag remover.

[0062] The specifications of the slag remover in this embodiment are: rod-shaped, diameter 5mm±1mm, length 10mm±1mm, compressive strength 2.5MPa, flexural strength 3.2MPa, volume density 1.0t / m 3 , initial foaming temperature: 1100℃. 1150℃ for 10min, bulk density 0.28t / m 3 The weight ratio of the coating material is about 2%.

[0063] The slag remover in this embodiment has the following application performance tests:

[0064] In the production of QT400-18AL rail iron plate castings in a 2-ton medium-frequency electric furnace, its specific applications include:

[0065] 1) During spheroidization, it is placed in the dam bag together with the spheroidizing agent and inoculant. After the molten iron is poured in, an insulation cover is added. During the spheroidization reaction, the slag remover quickly floats, foams, generates heat, and gathers slag, which plays the role of slag removal and covering insulation. The dosage is 9Kg / 2 tons of molten steel. Spheroidization, slag gathering, and slag removal are completed within 2 minutes.

[0066] 2) Before subcontracting, the slag remover is put into the surface of molten iron. After meeting the molten iron, it will quickly foam, generate heat, and gather slag, thus playing the role of slag removal and covering insulation. The dosage is 2.5Kg / 2 tons of molten steel, and slag gathering and slag removal can be completed within 2 seconds.

[0067] 3) After the transfer, sprinkle a certain amount of slag remover on the molten iron in the casting ladle, which will quickly foam, heat up, and gather slag, thus playing the role of slag removal and covering insulation. The molten iron in the casting ladle is 200 kg, and the dosage for each ladle is 100g, totaling 1kg. Inoculation, slag gathering, and slag removal can be completed within 2 seconds.

[0068] Compared with traditional slag removers, the dosage is reduced by 47%, the slag removal rate is increased by 40%, and the casting quality qualification rate is increased from 74% to 98.0%. Example

[0069] A sol-coated slag remover is prepared from a main material, an auxiliary material and a coating material.

[0070] The main material is made of the following raw materials in percentage by weight: 84% perlite powder, 2% expanded perlite powder, 5% bentonite, 0.5% silicon carbide powder, 7% graphite powder, and 1.5% aluminum fluoride;

[0071] The auxiliary materials are potassium humate and water. The amount of potassium humate is 2% of the main material, and the amount of water is 19% of the main material.

[0072] The coating material is aluminum phosphate sol. The volume density of aluminum phosphate sol is 1.47t / m 3 , pH value is 2.5, aluminum oxide content is 43%, and phosphorus pentoxide content is 42%.

[0073] The preparation method of the above-mentioned sol-coated slag remover comprises:

[0074] S1 Ingredients: Weigh the above raw materials by mass percentage, the total weight of the main material is 500 kg, potassium humate is 10 kg, and water is 95 kg. Slowly add potassium humate to water in equal amounts and stir evenly to prepare a potassium humate solution;

[0075] S2 Mixing: Mix the perlite powder, expanded perlite powder, bentonite, silicon carbide powder, graphite powder and aluminum fluoride evenly, add the potassium humate solution into the mixing process, mix into a slag remover mud for later use;

[0076] S3 molding: After the mixed deslagging agent mud is sealed and aged for 24 hours, it is put into an extrusion molding machine to extrude into deslagging agent mud strips with a diameter of 5 mm. The deslagging agent mud strips are cut into 10 mm long deslagging agent mud strip segments by a wire cutting machine;

[0077] S4 drying: the slag remover mud strips are dried in a mesh belt roller kiln at a temperature of 150°C for 60 minutes. After drying, the moisture content is less than 1%.

[0078] S5 Glue coating: The dried slag remover mud strips are passed through the coating material curtain glue coating device via a mesh belt, and the sol of the coating material is evenly coated on the outer periphery of the mud strips to form a coating layer with a thickness of 1 mm;

[0079] S6 low-temperature sintering: The slag remover strips coated with the coating material are sintered at low temperature in a mesh belt roller kiln. The sintering temperature is 350°C and the sintering time is 45 minutes. During the sintering, part of the bound water is removed from the perlite powder, and the aluminum phosphate sol is dehydrated and more tightly combined with the slag remover strips to obtain the slag remover.

[0080] The specifications of the slag remover in this embodiment are: rod-shaped, diameter 5mm±1mm, length 10mm±1mm, compressive strength 2.86MPa, flexural strength 3.5MPa, volume density 1.4t / m 3 , initial foaming temperature: 1130℃. 1150℃ for 10min, bulk density 0.43t / m 3 The weight ratio of the coating material is about 2%.

[0081] The slag remover in this embodiment has the following application performance tests:

[0082] In the casting production of gray cast iron pot blanks in a 1-ton medium-frequency electric furnace, its specific applications include:

[0083] 1) During spheroidization, it is placed in the dam bag together with the spheroidizing agent and inoculant. After the molten iron is poured in, an insulation cover is added. During the spheroidization reaction, the slag remover quickly floats, foams, generates heat, and gathers slag, which plays the role of slag removal and covering insulation. The dosage is 3.8Kg / 1 ton of molten steel. Spheroidization, slag gathering, and slag removal are completed within 2 minutes.

[0084] 2) Before subcontracting, the slag remover is put into the surface of molten iron. After meeting the molten iron, it will quickly foam, heat up, and gather slag, playing the role of slag removal and covering insulation. The dosage is 1.2Kg / 1 ton of molten steel, and slag gathering and slag removal can be completed within 2 seconds.

[0085] 3) After the transfer, sprinkle a certain amount of slag remover on the molten iron in the casting ladle, which will quickly foam, heat up, and gather slag, thus playing the role of slag removal and covering insulation. The molten iron in the casting ladle is 100 kg, and the dosage for each ladle is 40g, totaling 0.4 kg. Inoculation, slag gathering, and slag removal can be completed within 2 seconds.

[0086] 4) After pouring molten iron into the iron pot die-casting machine, there is no slag in the die-casting mold cavity, which completely changes the slag removal process before die-casting.

[0087] Compared with traditional slag removers, the dosage is reduced by 50%, the slag removal rate is increased by 30%, the process is reduced, the work efficiency is improved, and the casting quality qualification rate is increased from 84% to 99.5%.

[0088] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A sol-coated slag remover, characterized in that: It is prepared from main materials, auxiliary materials and coating materials, wherein the main materials are made of the following raw materials in percentage by weight: perlite powder 75%-85%, expanded perlite powder 2%-10%, bentonite 3%-10%, silicon carbide powder 0.5%-2%, graphite powder 5%-10%, aluminum fluoride 0.1%-2%; The auxiliary materials are potassium humate and water, the amount of potassium humate is 0.5-5% of the main material, and the amount of water is 18-25% of the main material; The amount of the coating material is 1-5% of the main material.

2. The sol-coated slag remover according to claim 1, characterized in that: The coating material is aluminum phosphate sol or aluminum sol.

3. The sol-coated slag remover according to claim 2, characterized in that: The volume density of the aluminum phosphate sol is 1.47t / m 3 , pH value is 2.5, aluminum oxide content is 43%, and phosphorus pentoxide content is 42%.

4. The sol-coated slag remover according to claim 1, characterized in that: The deslagging agent is in the shape of a rod, with a diameter of 4mm-6mm, a length of 5mm-10mm, a compressive strength greater than 1MPa, a flexural strength greater than 1.2MPa, and a bulk density of 0.8t / m 3 -1.4t / m 3 , the foaming temperature is 1120℃-1150℃.

5. The method for preparing the sol-coated slag remover according to claim 1, characterized in that: include: S1 ingredients: weigh the above raw materials according to weight percentage, slowly add potassium humate into water in equal amounts, and stir evenly to prepare a potassium humate solution; S2 Mixing: Mix the perlite powder, expanded perlite powder, bentonite, silicon carbide powder, graphite powder and aluminum fluoride evenly, add them into the potassium humate solution, and mix them into a slag remover slurry; S3 molding: After the mixed deslagging agent mud is sealed and aged for 24 hours, it is put into an extrusion molding machine to extrude into deslagging agent mud strips with a diameter of 4mm-6mm. The deslagging agent mud strips are cut into deslagging agent mud strip segments with a length of 5mm-10mm by a wire cutting machine; S4 drying: the slag remover mud strips are dried in a mesh belt roller kiln at a temperature of 150°C for 60-120 minutes. After drying, the moisture content is less than 1%. S5 Gluing: The dried slag remover mud strips pass through the coating material curtain glue coating device via a mesh belt, and the coating material will be evenly coated on the outer periphery of the mud strips to form a coating layer; S6 low-temperature sintering: The slag remover strips coated with the coating material are sintered at low temperature in a mesh belt roller kiln, the sintering temperature is 350°C-450°C, the sintering time is 25-50 minutes, and the sintering agent is obtained.

6. The method for preparing the sol-coated slag remover according to claim 5, characterized in that: The coating layer applied in S5 has a thickness of 1 mm.

7. Use of the sol-coated slag remover according to any one of claims 1 to 4 in ductile iron milling.