阅读说明：本技术 一种干式镁铬质捣打料 (Dry magnesium-chromium ramming mass ) 是由 任向阳 刘志强 翟耀杰 李新路 王炎超 翟柠崤 慕全定 姜东敏 翟鹏涛 于 2021-09-02 设计创作，主要内容包括：本发明属于耐火材料生产技术领域,具体涉及一种干式镁铬质捣打料。该干式镁铬质捣打料由干料和外加剂组成；所述干料由以下质量分数的组分组成：骨料65～73％,粉料15～26％,添加剂8～10％；所述骨料由废弃镁铬砖粉碎而成,其中Cr-(2)O-(3)含量16～20％；所述添加剂由固体水玻璃、硅微粉、六偏磷酸钠按重量比(3～5)：(3.5～4.5)：(0.5～1.0)组成；所述外加剂为液态热塑性酚醛树脂。本发明的干式镁铬质捣打料,本发明以废弃镁铬质残砖为主要原料,采用无水结合剂,在中低温下捣打料即能产生较大强度,在满足高温窑炉的使用要求的基础上,避免了对上部镁铬砖的损伤,延长窑炉的使用寿命。(The invention belongs to the technical field of refractory material production, and particularly relates to a dry magnesium-chromium ramming mass. The dry magnesium-chromium ramming mass consists of a dry material and an additive; the dry material comprises the following components in percentage by mass: 65-73% of aggregate, 15-26% of powder and 8-10% of additive; the aggregate is formed by crushing waste magnesia-chrome bricks, wherein Cr 2 O 3 The content is 16-20%; the additive is prepared from solid sodium silicate, silica micropowder and sodium hexametaphosphate in a weight ratio of (3-5): (3.5-4.5): (0.5-1.0); the additive is liquid thermoplastic phenolic resin. The dry magnesia-chromite ramming mass takes waste magnesia-chromite residual bricks as main raw materials, adopts the anhydrous bonding agent, can generate higher strength at medium and low temperature, avoids the damage to the magnesia-chromite bricks at the upper part on the basis of meeting the use requirement of a high-temperature kiln, and prolongs the service life of the kiln.)

1. A dry-type magnesia-chrome ramming mass is characterized by comprising a dry material and an additive;

the dry material comprises the following components in percentage by mass: 65-73% of aggregate, 15-26% of powder and 8-10% of additive; the aggregate is formed by crushing waste magnesia-chrome bricks, wherein Cr₂O₃The content is 16-20%; the additive is prepared from solid sodium silicate, silicon micropowder and hexametaphosphateSodium phosphate is prepared from the following components in parts by weight (3-5): (3.5-4.5): (0.5-1.0);

the additive is liquid thermoplastic phenolic resin.

2. The dry magnesium-chromium ramming mass according to claim 1, wherein the dry mass comprises the following components in percentage by mass: 67-73% of aggregate, 17-25% of powder and 8-10% of additive.

3. The dry magnesium-chromium ramming mass according to claim 1 or 2, wherein the weight ratio of the solid water glass, the silicon micropowder and the sodium hexametaphosphate is as follows: (3.9-4.7): (3.5-4.5): (0.6-0.8).

4. The dry magnesium-chromium ramming mass according to claim 1, wherein the aggregate has a particle size of 8mm or less and the powder has a particle size of 0.074mm or less.

5. The dry magnesium-chromium ramming mass according to claim 4, wherein the aggregate is prepared from three particle size fractions of 5-8 mm, 3-5 mm and <3mm, and the weight ratio is (13-18): (19-25): (30-38).

6. The dry magnesium-chromium ramming mass according to claim 5, wherein the mass ratio of particles with three particle sizes of 5-8 mm, 3-5 mm and <3mm is (13-18): (19-22): (33-38) grading.

7. The dry magnesia-chromia ramming mass according to claim 1 or 4, wherein the powder consists of sintered magnesia and waste magnesia-chromia brick powder in the weight ratio of (11-15): (6-10.2).

8. The dry magnesia-chrome ramming mass of claim 7, wherein the mass content of MgO in the sintered magnesia is not less than 90%.

9. The dry magnesium-chromium ramming mass according to claim 1, wherein the dry mass and the additive are mixed uniformly and then rammed and used at a working temperature of 500-700 ℃.

Technical Field

The invention belongs to the technical field of refractory material production, and particularly relates to a dry magnesium-chromium ramming mass, in particular to a dry magnesium-chromium ramming mass for a nonferrous metallurgy high-temperature furnace.

Background

In non-ferrous metal smelting high temperature kiln, such as reverberatory furnace, etc., magnesia-chrome brick with anti-corrosion performance is used as working lining, and between the working lining and the high temperature furnace body, a packing layer with certain thickness is laid, and the packing material is ramming material or casting material.

The packing layer plays the following roles: (1) filling a gap between the magnesium-chromium working lining and the furnace bottom, and buffering stress generated between the magnesium-chromium material and the high-temperature furnace body due to temperature change; (2) when unexpected melt leakage occurs due to smelting operation, the quality of the magnesium-chromium refractory bricks and other factors in the using process, the filler layer can prevent the melt from directly contacting the furnace body within a certain time, and personal injury and property loss caused by leakage of high-temperature melt are prevented.

The poured layer or ramming material layer is generally made of magnesium-chromium raw materials. In the long-term use process of some nonferrous metal smelting high-temperature kilns using magnesia-chrome bricks as working linings, a large amount of used residual bricks are generated, and the bricks can not be processed after being piled up all the year round, thus being easy to cause environmental pollution; in addition, for convenience of construction, a certain amount of moisture is usually added in the packing layer during laying construction, and the alkaline refractory material is easy to hydrate, so that the performance of the working lining magnesia-chrome brick is reduced due to hydration, and even the service life of the furnace lining of the furnace is reduced.

The conventional dry ramming mass has low strength at medium and low temperature, and is difficult to meet the requirement of building a kiln lining at the upper part of the material, particularly the requirement of building the kiln lining again at the upper part after the material is used at the working temperature of about 600 ℃ (the condition of replacing the kiln lining).

Disclosure of Invention

The invention aims to provide a dry magnesium-chromium ramming mass, which solves the problem that the conventional ramming mass has lower strength at medium and low temperature.

In order to achieve the purpose, the technical scheme adopted by the invention is as follows:

a dry-type magnesium-chromium ramming mass comprises a dry material and an additive;

the dry material comprises the following components in percentage by mass: 65-73% of aggregate, 15-26% of powder and 8-10% of additive; the aggregate is formed by crushing waste magnesia-chrome bricks, wherein Cr₂O₃The content is 16-20%; the additive is prepared from solid sodium silicate, silica micropowder and sodium hexametaphosphate in a weight ratio of (3-5): (3.5-4.5): (0.5-1.0);

the additive is liquid thermoplastic phenolic resin.

The dry magnesia-chromite ramming mass takes waste magnesia-chromite residual bricks as main raw materials, adopts the anhydrous bonding agent, can generate higher strength at medium and low temperature, avoids the damage to the magnesia-chromite bricks at the upper part on the basis of meeting the use requirement of a high-temperature kiln, and prolongs the service life of the kiln.

In addition, the invention adopts the waste magnesia-chrome bricks as the main raw materials, realizes the recycling of waste resources, saves precious raw materials and reduces the environmental pollution. Meanwhile, the used raw materials are low in cost, the production cost is reduced, the economic benefit of enterprises is improved, and the method has a wide market application prospect.

Preferably, the dry material consists of the following components in percentage by mass: 67-73% of aggregate, 17-25% of powder and 8-10% of additive.

Preferably, the weight ratio of the solid water glass, the silicon micropowder and the sodium hexametaphosphate is as follows: (3.9-4.7): (3.5-4.5): (0.6-0.8).

Preferably, the grain diameter of the aggregate is less than or equal to 8mm, and the grain diameter of the powder is less than or equal to 0.074 mm. Preferably, the aggregate is prepared by grading three particle sizes of 5-8 mm, 3-5 mm and <3mm, and the weight ratio is (13-18): (19-25): (30-38). More preferably, the mass ratio of particles with three particle diameters of 5-8 mm, 3-5 mm and <3mm is (13-18): (19-22): (33-38) grading.

Preferably, the powder material is prepared from sintered magnesia and waste magnesia-chrome brick powder in a weight ratio of (11-15): (6-10.2). The magnesite-chrome brick is formed by high-temperature sintering (sintering temperature is higher than that of the magnesite brick) of magnesite and chrome ore raw materials. The waste magnesite-chrome bricks are wastes of the magnesite-chrome bricks used under the condition of high temperature for a long time, can be regarded as barren materials, and have much lower sintering activity than magnesite. The addition of the sintered magnesia can enhance the sintering activity and viscosity of the ramming mass, and the sintered magnesia and the waste magnesia-chrome brick powder are compounded according to the proportion, so that the waste material is reasonably utilized, and the improvement of the medium-low temperature strength of the ramming mass is facilitated.

Further preferably, the mass content of MgO in the sintered magnesite is more than or equal to 90%.

Preferably, the dry materials and the additives are uniformly mixed and then are rammed and constructed, and the dry materials and the additives are used at the working temperature of 500-700 ℃.

Detailed Description

The invention adopts waste magnesia-chrome bricks as main raw materials, and additives are added to prepare the dry magnesia-chrome ramming mass.

The dry magnesium-chromium ramming mass adopts an anhydrous bonding agent, has high medium-low temperature bonding strength, and prolongs the service life of a furnace lining. The raw materials used in the present invention are all commercially available products or waste resources, and the following description will be given of the case of the main raw materials:

waste magnesia-chrome brick of Cr₂O₃The content is 16-20%.

The content of MgO in the sintered magnesite is more than or equal to 90 percent.

Solid water glass, modulus 3.00, Na₂The content of O is 18.5-22.5%.

Fine silicon powder, SiO₂The content is more than or equal to 90 percent.

The liquid thermoplastic phenolic resin has the viscosity of 5000-.

In the present invention, "%" is mass percent unless otherwise specified.

The following examples are provided to further illustrate the practice of the invention.

Concrete example of dry-type magnesia-chrome ramming mass

Example 1

The dry magnesium-chromium ramming mass of the embodiment comprises, by mass, 70% of aggregate, 21.2% of powder, 8.8% of additive, and 4% of additive.

The raw material of the aggregate is waste magnesia-chrome brick; the grain size of the aggregate is less than or equal to 8mm, wherein the aggregate with the size of 5 mm-8 mm accounts for 18%, the aggregate with the size of 3 mm-5 mm accounts for 19%, and the aggregate with the size of <3mm accounts for 33% of the total weight of the aggregate.

The raw materials of the powder are waste magnesia-chrome brick powder and sintered magnesia; the grain diameter of the powder is less than or equal to 0.074 mm. The usage of the sintered magnesia powder is 11 percent, and the usage of the waste magnesia-chrome brick powder is 10.2 percent.

The additive comprises the following components in percentage by weight: 4% of solid sodium silicate powder, 4% of silicon micropowder and 0.8% of sodium hexametaphosphate.

The additive is liquid thermoplastic phenolic resin, and the dosage of the additive is 4%.

The preparation method comprises the following steps:

removing the obviously polluted part of the waste magnesia-chrome brick, and crushing and processing the waste magnesia brick and the sintered magnesia into aggregate and powder meeting the granularity requirement.

Weighing aggregate, powder and additive according to the specified mass, and premixing the weighed additive.

Weighing liquid thermoplastic phenolic resin.

And adding the weighed aggregate, powder and additive into a forced stirrer for mixing, adding the additive in the mixing process, and forcibly stirring for 10 minutes for later use.

Example 2

The dry magnesium-chromium ramming mass of the embodiment comprises 73 mass percent of aggregate, 17 mass percent of powder, 10 mass percent of additive and 3.5 mass percent of additive.

The raw material of the aggregate is waste magnesia-chrome brick; the grain size of the aggregate is less than or equal to 8mm, wherein the aggregate with the size of 5 mm-8 mm accounts for 13%, the aggregate with the size of 3 mm-5 mm accounts for 22%, and the aggregate with the size of <3mm accounts for 38% of the total amount of the aggregate.

The raw materials of the powder are waste magnesia-chrome brick powder and sintered magnesia; the grain diameter of the powder is less than or equal to 0.074 mm. The usage of the sintered magnesia powder is 11 percent, and the usage of the waste magnesia-chrome brick powder is 6 percent.

The additive comprises the following components in percentage by weight: 4.7 percent of solid sodium silicate powder, 4.5 percent of silicon micropowder and 0.8 percent of sodium hexametaphosphate.

The additive is liquid thermoplastic phenolic resin, and the dosage of the additive is 3.5 percent.

The preparation method is the same as that of example 1.

Example 3

The dry magnesium-chromium ramming mass of the embodiment comprises, by mass, 67% of aggregate, 25% of powder, 8% of additive, and 5% of additive.

The aggregate is made of waste magnesia-chrome bricks; the particle size of the aggregate is less than or equal to 8mm, wherein the aggregate with the size of 5 mm-8 mm accounts for 14%, the aggregate with the size of 3 mm-5 mm accounts for 20%, and the aggregate with the size of <3mm accounts for 33% of the total amount of the aggregate.

The raw materials of the powder are waste magnesia-chrome brick powder and sintered magnesia; the grain diameter of the powder is less than or equal to 0.074 mm. The usage of the sintered magnesia powder is 15 percent, and the usage of the waste magnesia-chrome brick powder is 10 percent.

The additive comprises the following components in percentage by mass: 3.9 percent of solid sodium silicate powder, 3.5 percent of silicon micropowder and 0.6 percent of sodium hexametaphosphate.

The additive is liquid thermoplastic phenolic resin, and the dosage of the additive is 5 percent.

The preparation method is the same as that of example 1.

Second, comparative example

Comparative example 1

The dry magnesium-chromium ramming mass of the embodiment comprises, by mass, 70% of aggregate, 20% of powder, 10% of additive, and 4% of additive.

The raw material of the aggregate is waste magnesia-chrome brick; the grain size of the aggregate is less than or equal to 8mm, wherein the aggregate with the size of 5 mm-8 mm accounts for 18%, the aggregate with the size of 3 mm-5 mm accounts for 19%, and the aggregate with the size of <3mm accounts for 33% of the total weight of the aggregate.

The raw materials of the powder are waste magnesia-chrome brick powder and sintered magnesia; the grain diameter of the powder is less than or equal to 0.074 mm. The usage of the sintered magnesia powder is 10 percent, and the usage of the waste magnesia-chrome brick powder is 10 percent.

The additive comprises the following components in percentage by weight: 2% of solid sodium silicate powder, 4% of silicon micropowder, 1.0% of sodium hexametaphosphate and 3% of light-burned magnesium powder.

The additive is liquid thermoplastic phenolic resin, and the dosage of the additive is 4%.

The preparation method is the same as that of example 1.

Comparative example 2

The dry magnesium-chromium ramming mass of the embodiment comprises, by mass, 70% of aggregate, 21% of powder, 9% of additive, and 4% of additive.

The raw material of the aggregate is waste magnesia-chrome brick; the grain size of the aggregate is less than or equal to 8mm, wherein the aggregate with the size of 5 mm-8 mm accounts for 18%, the aggregate with the size of 3 mm-5 mm accounts for 19%, and the aggregate with the size of <3mm accounts for 33% of the total weight of the aggregate.

The raw materials of the powder are waste magnesia-chrome brick powder and sintered magnesia; the grain diameter of the powder is less than or equal to 0.074 mm. The usage of the sintered magnesia powder is 11 percent, and the usage of the waste magnesia-chrome brick powder is 10 percent.

The additive comprises the following components in percentage by weight: 4% of solid sodium silicate powder, 2% of silicon micropowder, 1.0% of sodium hexametaphosphate and 2.0% of boric acid.

The additive is liquid thermoplastic phenolic resin, and the dosage of the additive is 4%.

The preparation method is the same as that of example 1.

Comparative example 3

The dry magnesium-chromium ramming mass of the embodiment comprises, by mass, 70% of aggregate, 22% of powder, 8% of additive, and 4% of additive.

The raw material of the aggregate is waste magnesia-chrome brick; the grain size of the aggregate is less than or equal to 8mm, wherein the aggregate with the size of 5 mm-8 mm accounts for 18%, the aggregate with the size of 3 mm-5 mm accounts for 19%, and the aggregate with the size of <3mm accounts for 33% of the total weight of the aggregate.

The raw materials of the powder are waste magnesia-chrome brick powder and sintered magnesia; the grain diameter of the powder is less than or equal to 0.074 mm. The usage of the sintered magnesia powder is 12 percent, and the usage of the waste magnesia-chrome brick powder is 10 percent.

The additive comprises the following components in percentage by weight: 3% of solid sodium silicate powder, 3% of silicon micropowder and 2.0% of sodium hexametaphosphate.

The additive is liquid thermoplastic phenolic resin, and the dosage of the additive is 4%.

The preparation method is the same as that of example 1.

Third, Experimental example

After the materials of the examples were subjected to the ramming operation, the rammed materials were sampled and tested, and the results are shown in table 1 below.

TABLE 1 physical Properties test results for ramming masses

The results in Table 1 show that when the powder is dried at 110 ℃ for 24h, the normal temperature bonding agent acts, the compressive strength reaches 39-50 MPa, and the volume density is 2.61-2.65 g/cm³(ii) a At the working temperature of 600 ℃, the bonding strength of the conventional ramming mass is in a lower range and cannot meet the requirement of building a kiln lining on the upper part of the ramming mass, and the compressive strength of the ramming mass of the invention at the temperature still reaches 21-25 MPa and is in a higher compressive strength range, so that the ramming mass can meet the first building of the kiln lining or the second building process after the kiln lining is replaced.