Environmentally friendly tundish dry material and preparation method thereof

Abstract

The present invention relates to an environmentally friendly intermediate bag dry material, comprising the following components in parts by weight: 15 to 25 parts of magnesia with a particle size of 3 to 5 mm; 70 to 100 parts of magnesia with a particle size of 0.085 to 3 mm; 25 to 45 parts of magnesia with a particle size of ≤0.085 mm; 10 to 15 parts of a composite binder; 5 to 8 parts of alumina powder; 3 to 5 parts of metal silicon powder; and 3 to 5 parts of bentonite. First, the ingredients are weighed and mixed according to the above ratio, and magnesia with a particle size of 3 to 5 mm, magnesia with a particle size of 0.085 to 3 mm, and magnesia with a particle size of ≤0.085 mm are sequentially added into a mixer for premixing and uniform mixing; then, alumina powder, metal silicon powder, and bentonite are sequentially added into the mixer for uniform mixing; finally, the composite binder is added into the mixer for uniform mixing to obtain a dry material. The intermediate bag dry material of the present invention adopts a composite binder to replace phenolic resin, so as to avoid the generation of harmful gases and environmental pollution during use.

Description

Technical Field

[0001] The invention relates to the field of refractory materials, in particular to an environmentally friendly tundish dry material and a preparation method thereof. Background Art

[0002] Since the birth of the continuous casting tundish, the tundish has played an irreplaceable role, and dry materials are the basis for protecting its normal and safe operation. Dry materials have the advantages of convenient construction, fast heating speed, long life and easy detachment.

[0003] At present, phenolic resin is usually used as a binder in the dry material of the tundish. After low-temperature heat treatment, phenolic resin can form a strong three-dimensional grid structure with high bonding strength. However, the residual carbon and hydrogen produced by phenolic resin during the baking process of dry materials will increase carbon and hydrogen in the molten steel, affecting the quality of the steel billet, and will produce a large amount of harmful and irritating gases, polluting the environment and affecting the health of operators, so its use is restricted. Summary of the invention

[0004] In order to overcome the defects of the prior art, the technical problem solved by the present invention is to provide an environmentally friendly tundish dry material and a preparation method thereof. The tundish dry material of the present invention adopts a composite binder to replace phenolic resin to avoid the generation of harmful gases and environmental pollution during use.

[0005] In order to achieve the above object, the present invention adopts the following technical solutions:

[0006] An environmentally friendly tundish dry material comprises the following components in parts by weight:

[0007] 15-25 parts of magnesia with a particle size of 3-5 mm;

[0008] 70-100 parts of magnesia with a particle size of 0.085-3 mm;

[0009] 25-45 parts of magnesia with a particle size of ≤0.085 mm;

[0010] Composite binder, 10-15 parts;

[0011] Alumina powder, 5-8 parts;

[0012] Metal silicon powder, 3-5 parts;

[0013] Bentonite, 3 to 5 parts.

[0014] The composite binder is a mixture of rosin and calcium sulfate containing crystal water.

[0015] The calcium sulfate addition ratio of the rosin and crystal water is 1: (2-3).

[0016] The magnesia is any one of high-purity sintered magnesia or fused magnesia, wherein MgO is ≥ 95%.

[0017] The silicon content of the metal silicon powder is ≥98%; the particle size of the metal silicon powder is ≤325 meshes.

[0018] The Al2O3 content of the alumina micropowder is ≥98%; and the particle size of the alumina micropowder is ≤325 meshes.

[0019] A method for preparing an environmentally friendly tundish dry material comprises the following steps:

[0020] First, weigh and mix the ingredients according to the above ratio, add magnesia with a particle size of 3 to 5 mm, magnesia with a particle size of 0.085 to 3 mm, and magnesia with a particle size of ≤0.085 mm into a mixer in sequence for premixing and mixing evenly;

[0021] Then, add alumina powder, metallic silicon powder and bentonite into the mixer in sequence and mix them evenly;

[0022] Finally, the composite binder is added into a blender and mixed evenly to obtain a dry material.

[0023] Compared with the prior art, the present invention has the following beneficial effects:

[0024] The present invention adopts a composite binder to replace phenolic resin, which does not generate harmful irritating gas during application and is more environmentally friendly; the calcium sulfate of crystal water in the composite binder is dehydrated to form a gel, and is deposited on the surface of magnesia sand and their fine powder of the refractory aggregate to make it cemented, hardened, and obtain strength; the rosin reduces the surface tension of the liquid-gas interface, promotes the formation and stability of bubbles, that is, the rosin can form a closed pore structure in the refractory material, thereby enhancing the fire resistance of the material. The calcium sulfate of crystal water and the rosin are used in combination, and the advantages of the two binders are combined, so that the calcium sulfate of crystal water is better filled in the material after being dehydrated and gelled, so that the obtained dry material has higher strength and fire resistance. DETAILED DESCRIPTION

[0025] The specific embodiments of the present invention are further described below:

[0026] Example 1

[0027] The present invention provides an environmentally friendly tundish dry material, comprising the following components in parts by weight:

[0028] 18 parts of magnesia with a particle size of 3 to 5 mm;

[0029] 75 parts of magnesia with a particle size of 0.085 to 3 mm;

[0030] Magnesium sand with a particle size of ≤0.085 mm, 25 parts;

[0031] Composite binder, 11 parts;

[0032] Alumina powder, 5 parts;

[0033] Metal silicon powder, 3 parts;

[0034] Bentonite, 3 parts.

[0035] The composite binder is a mixture of rosin and calcium sulfate containing crystal water.

[0036] The calcium sulfate addition ratio of the rosin and crystal water is 1:2.

[0037] The magnesia is any one of high-purity sintered magnesia or fused magnesia, wherein MgO is ≥ 95%.

[0038] The silicon content of the metal silicon powder is ≥98%; the particle size of the metal silicon powder is ≤325 meshes.

[0039] The Al2O3 content of the alumina micropowder is ≥98%; and the particle size of the alumina micropowder is ≤325 meshes.

[0040] A method for preparing an environmentally friendly tundish dry material comprises the following steps:

[0041] First, weigh and mix the ingredients according to the above ratio, add magnesia with a particle size of 3 to 5 mm, magnesia with a particle size of 0.085 to 3 mm, and magnesia with a particle size of ≤0.085 mm into a mixer in sequence for premixing and mixing evenly;

[0042] Then, add alumina powder, metallic silicon powder and bentonite into the mixer in sequence and mix them evenly;

[0043] Finally, the composite binder is added into a blender and mixed evenly to obtain a dry material.

[0044] Example 2

[0045] The present invention provides an environmentally friendly tundish dry material, comprising the following components in parts by weight:

[0046] 20 parts of magnesia with a particle size of 3 to 5 mm;

[0047] 85 parts of magnesia with a particle size of 0.085 to 3 mm;

[0048] Magnesia with a particle size of ≤0.085 mm, 40 parts;

[0049] composite binder, 13 parts;

[0050] Alumina powder, 6 parts;

[0051] Metallic silicon powder, 5 parts;

[0052] Bentonite, 4 parts.

[0053] The composite binder is a mixture of rosin and calcium sulfate containing crystal water.

[0054] The calcium sulfate addition ratio of the rosin and crystal water is 1:2.5.

[0055] The magnesia is any one of high-purity sintered magnesia or fused magnesia, wherein MgO is ≥ 95%.

[0056] The silicon content of the metal silicon powder is ≥98%; the particle size of the metal silicon powder is ≤325 meshes.

[0057] The Al2O3 content of the alumina micropowder is ≥98%; and the particle size of the alumina micropowder is ≤325 meshes.

[0058] A method for preparing an environmentally friendly tundish dry material comprises the following steps:

[0059] First, weigh and mix the ingredients according to the above ratio, add magnesia with a particle size of 3 to 5 mm, magnesia with a particle size of 0.085 to 3 mm, and magnesia with a particle size of ≤0.085 mm into a mixer in sequence for premixing and mixing evenly;

[0060] Then, add alumina powder, metallic silicon powder and bentonite into the mixer in sequence and mix them evenly;

[0061] Finally, the composite binder is added into a blender and mixed evenly to obtain a dry material.

[0062] The preferred embodiments of the present invention are described in detail above, but the present invention is not limited to the specific details in the above embodiments. Within the technical concept of the present invention, the technical solution of the present invention can be subjected to a variety of simple modifications, and these simple modifications all belong to the protection scope of the present invention. It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any suitable manner without contradiction. In order to avoid unnecessary repetition, the present invention will not further describe various possible combinations. In addition, the various different embodiments of the present invention can also be arbitrarily combined, as long as they do not violate the concept of the present invention, they should also be regarded as the contents disclosed by the present invention.

Claims

1. An environmentally friendly tundish dry material, characterized in that: Contains the following components in parts by weight: 15-25 parts of magnesia with a particle size of 3-5 mm; 70-100 parts of magnesia with a particle size of 0.085-3 mm; 25-45 parts of magnesia with a particle size of ≤0.085 mm; Composite binder, 10-15 parts; Alumina powder, 5-8 parts; Metal silicon powder, 3-5 parts; Bentonite, 3 to 5 parts.

2. The environmentally friendly tundish dry material according to claim 1, characterized in that: The composite binder is a mixture of rosin and calcium sulfate containing crystal water.

3. The environmentally friendly dry material for tundish according to claim 2, characterized in that: The calcium sulfate addition ratio of the rosin and crystal water is 1: (2-3).

4. The environmentally friendly tundish dry material according to claim 1, characterized in that: The magnesia is any one of high-purity sintered magnesia or fused magnesia, wherein MgO is ≥ 95%.

5. The environmentally friendly tundish dry material according to claim 1, characterized in that: The silicon content of the metal silicon powder is ≥98%; the particle size of the metal silicon powder is ≤325 meshes.

6. The environmentally friendly dry tundish material according to claim 1, characterized in that: The Al2O3 content of the alumina micropowder is ≥98%; and the particle size of the alumina micropowder is ≤325 meshes.

7. A method for preparing an environmentally friendly tundish dry material as claimed in claim 1, comprising the following steps: First, weigh and mix the ingredients according to the above ratio, add magnesia with a particle size of 3 to 5 mm, magnesia with a particle size of 0.085 to 3 mm, and magnesia with a particle size of ≤0.085 mm into a mixer in sequence for premixing and mixing evenly; Then, add alumina powder, metallic silicon powder and bentonite into the mixer in sequence and mix them evenly; Finally, the composite binder is added into a blender and mixed evenly to obtain a dry material.