CN118271102B - Kiln coating material for high-viscosity refractory bricks, preparation method and application - Google Patents

Abstract

The invention discloses a kiln coating material of high-viscosity refractory bricks and a preparation method and application thereof, wherein the kiln coating material consists of 40-55% of silicate minerals, 22-25% of paint waste, 5-7% of magnesia alumina spinel, 0.3-0.5% of tackifying paint and the balance of aluminate minerals in percentage by weight; the preparation method comprises the steps of S1, raw material preparation, S2, raw material mixing; the application method is that the coating is applied to the dangerous waste rotary kiln; the invention has better promotion effect on the viscosity of the kiln coating material of the refractory brick by adopting the tackifying coating, the surface hardness and the wear resistance of the kiln coating material can be improved by the silk fibroin at high temperature, and the kiln coating material prepared by using the modified silk fibroin-based alkyd resin as the tackifying coating has better thermal stability and viscosity.

Description

High-viscosity refractory brick kiln lining material and preparation method and application thereof

Technical Field

The invention relates to the technical field of kiln lining materials, and in particular to a high-viscosity refractory brick kiln lining material and a preparation method and application thereof.

Background Art

The cement raw material adheres and combines on the surface of the refractory bricks in the burning zone and transition zone to form a material layer with a certain strength, which is called the kiln skin. The kiln skin is formed by the C ₃ S and C ₂ S as a fixed skeleton and the melt C ₃ A and C ₄ AF filled between these grains, as well as MgO, Na ₂ O, K ₂ O and SO _3. The ability of refractory bricks and cement raw materials to react appropriately to form a kiln skin is called the kiln skin hanging ability.

At a certain temperature, the melt contained in clinker with a certain composition has a certain amount and viscosity, which determines the particle size of the clinker at that time, the difficulty of sticking to the kiln skin on the brick surface, the fastness of fixation, and the degree of change of the melt quantity and viscosity under the change of kiln temperature, that is, the degree of stability of the kiln skin. Obviously, only when the composition of the kiln material is stable and appropriate, and adapted to the kiln temperature at the location, the position of the flame and the kiln temperature must also be stable, can a melt with an appropriate amount and viscosity be formed. When the kiln temperature reaches a certain value, a melt is generated in the kiln material (including fly ash, etc.), chemically adsorbed and physically adhered on the brick surface, and then penetrated into the brick and reacted with the components in the brick. This is the formation stage of the kiln skin.

The infiltrate solidifies at a temperature not exceeding 1200℃, producing mechanical anchoring, which is the adhesion and fixation stage of the kiln skin, thus forming the initial layer of the kiln skin. Certain elements in the raw material will also penetrate to a certain depth along the microscopic gaps of the refractory bricks, so that the refractory bricks, like a snowball, gradually form a thicker and more stable kiln skin layer by layer on the basis of this initial kiln skin. This layer of material is of positive significance for protecting refractory bricks. It can effectively resist wear, effectively insulate, and effectively block thermal erosion and chemical erosion.

The formula of the kiln lining material is mainly based on low-melting-point silicon materials such as sand and glass, which are easy to form a liquid phase and increase adhesion, and can adhere well to the smooth surface of refractory bricks; at the same time, it contains a certain amount of iron products to increase the strength of the kiln lining and effectively resist the friction and impact of hazardous waste on refractory bricks when rotating in the rotary kiln; the viscosity of the kiln lining material in the prior art is increased by converting it into a liquid phase. Based on this, the present invention provides a high-viscosity refractory brick kiln lining material and its preparation method and application.

Summary of the invention

In order to solve the above technical problems, the present invention provides a high-viscosity refractory brick kiln lining material, a preparation method and an application thereof.

The technical solution of the present invention is: a high-viscosity refractory brick kiln lining material, which is composed of 40-55% silicate minerals, 22-25% paint waste, 5-7% magnesia-alumina spinel, 0.3-0.5% adhesion-enhancing coating and the balance of aluminate minerals by weight percentage;

Wherein, the silicate mineral is composed of C ₃ S and C ₂ S in a mass ratio of 3-5:1.8-2;

The viscosity-enhancing coating is composed of modified silk fibroin-based alkyd resin, yellow clay, montmorillonite, and deionized water in a mass ratio of 3.2-6.4:17-19:6.2-6.5:20-25;

The magnesium aluminum spinel is composed of Al ₂ O ₃ , ZrO ₂ ·SiO ₂ , Fe ₂ O ₃ and MgO in a mass ratio of 52.4-53.6: 0.7-0.9: 43-45: 0.5-3.9;

The aluminate mineral is composed of C ₃ A and C ₄ AF in a mass ratio of 1:1;

Description: The present invention promotes the viscosity of silicate minerals in refractory brick kiln lining materials by using a thickening coating. Silk fibroin will gradually carbonize at high temperature to form a protective film, which can protect the inner layer of the green body from high temperature ablation and improve the surface hardness and wear resistance of the green body. The kiln lining material prepared by using the modified silk fibroin-based alkyd resin as a thickening coating not only has good thermal stability, but also further enhances the bonding ability of the kiln lining material through chemical bonding with the silicate melt. Although the alkyd resin coating can make the silicate mineral have good adhesion and wear resistance, it is easy to deteriorate at high temperature, thereby affecting the adhesion ability. The silk fibroin-based alkyd resin acts on the silicate mineral at high temperature so that it can still form a stable, high-viscosity kiln lining, and has good wear resistance, heat insulation and chemical erosion capabilities.

Furthermore, the preparation method of the modified silk fibroin-based alkyd resin is as follows: 25 to 40 g of silk fibroin is added to 180 to 200 mL of an acetone solvent having a mass concentration of 48 to 52% and stirred at a speed of 300 to 350 rpm for 25 to 30 minutes to obtain a silk fibroin solution; ultrasonically mixing the alkyd resin: fluorocarbon branched chain urethane oil additive: ammonium polyphosphate at a weight ratio of 40 to 45: 12.7 to 14.6: 10 to 15 to obtain a resin mixture;

2/3 of the silk fibroin solution is taken for later use, a resin mixture is prepared according to a weight ratio of resin mixture: silk fibroin solution of 8-10:7.6-8.5, and the resin mixture is added dropwise to the silk fibroin solution at a rate of 3-5 drops/min to obtain a mixture A; then the remaining 1/3 of the silk fibroin solution is added dropwise to the mixture A at a rate of 8-10 drops/min, and mixed to obtain a modified silk fibroin-based alkyd resin;

The parameters of the ultrasonic mixing are ultrasonic frequency: 32-40 kHz, and ultrasonic time: 8-10 min.

Description: Mixing fluorocarbon branched urethane oil additives with alkyd resin can further optimize the adhesion, leveling and wettability of the coating, and the cost of using fluorocarbon branched urethane oil additives is lower than that of other modified materials. Mixing alkyd resin with fluorocarbon branched urethane oil additives and ammonium polyphosphate and then dropping them into the silk fibroin solution can give full play to the modification effect of fluorocarbon branched urethane oil additives on alkyd resin. The addition of ammonium polyphosphate can effectively flame retard alkyd resin. At the same time, the excellent properties of silk fibroin can improve the leveling and wettability of the tackifying coating, so as to better act on silicate minerals and further improve the kiln skin performance of the kiln skin material. Adding the remaining silk fibroin solution to the mixed solution A can further enhance the hardness, impact resistance and wear resistance of the tackifying coating, and improve its waterproof performance and durability.

Furthermore, the particle size of the magnesium-aluminum spinel is 1 to 3 mm, and the particle size of the silicate mineral and the aluminate mineral is 0.05 to 0.074 mm;

Note: By limiting the particle size of the above materials, it is possible to ensure that the surface energy of the materials is larger, thereby increasing the viscosity of the kiln lining. The difference in particle size of silicate minerals, aluminate minerals and magnesium-aluminum spinel can also make small particles fill the gaps between large particles during the mixing process of the materials, forming a tighter arrangement, thereby increasing the viscosity of the material.

The present invention also provides a method for preparing a high-viscosity refractory brick kiln lining material, comprising the following steps:

S1. Raw material preparation

S1-1, take 1/3 to 2/3 of the magnesium aluminum spinel and the aluminate mineral and mix them at room temperature for 30 to 50 minutes to obtain a mixture I, and mix the remaining magnesium aluminum spinel with silicate minerals and paint waste at room temperature for 20 to 30 minutes to obtain a mixture II, and divide the mixture II into 3 to 5 portions for standby use;

S1-2, take 3/4 of yellow clay, the whole amount of montmorillonite and 1/4 to 3/4 of deionized water and stir and mix at 150 to 170 rpm for 15 to 20 minutes to obtain base material A; then microwave the remaining yellow clay, the whole amount of modified silk fibroin-based alkyd resin and the remaining deionized water for 15 to 20 minutes to obtain base material B; finally, spray the base material B on the surface of the base material A at a rate of 30 to 50 mL/min, mix well to obtain a tackifying coating, and set aside;

S2. Raw material mixing

The mixed material I obtained in step S1 is transferred to a ball mill with a rotation speed of 370-400 rpm, the initial temperature of the ball mill is 50-60°C, the temperature of the ball mill is increased at a rate of 3-5°C/min, and the temperature is raised to 85-90°C and then kept warm for 1.5-2h. During the heating process, the mixed material II is added to the ball mill once every 20-30min until the addition of the mixed material II is completed; during the insulation process, 15-20mL of the viscosity-increasing coating is added to the ball mill every 20-30min until the insulation treatment is completed, thereby obtaining a kiln skin material;

Description: The preparation method of the above-mentioned kiln lining material mixes aluminate minerals and silicate minerals with magnesium aluminum spinel respectively and then adds them in batches, which can effectively improve the mixing uniformity and achieve better mixing effect. At the same time, the viscosity-increasing filler is prepared by using two parts of base materials containing modified silk fibroin-based alkyd resin and not containing modified silk fibroin-based alkyd resin respectively and then mixed, which can make the modified silk fibroin-based alkyd resin better dispersed in yellow clay and montmorillonite, and further improve the viscosity of the kiln lining material; gradually adding mixture II during the heating process can promote the sintering of the material by step-by-step heating, which helps to improve the density and stability of the kiln lining material; adding viscosity-increasing coating in the final insulation process can make the coating better fill the surface of the raw material under high temperature to form a stable and high-viscosity kiln lining material.

Further, in step S1-2, the microwave treatment parameters are: microwave irradiation intensity is 100-120W, microwave irradiation temperature is 75-100°C;

Note: Under the above parameters, microwave treatment can promote the mixing of alkyd resin and silk fibroin and improve the uniformity and adhesion of the coating.

The invention also provides an application method of a high-viscosity refractory brick kiln lining material, which is applied to coating a hazardous waste rotary kiln.

Furthermore, the coating method is:

First, the inner wall of the hazardous waste rotary kiln is preheated to 180-190°C for 0.5-1h; then, within the first 24h of opening the kiln, 60-70% of the normal output of the hazardous waste rotary kiln is fed by electrostatic spraying, and the coating thickness is maintained at 1-3mm; after more than 24h, the feeding amount is adjusted by increasing 5-10% every 8-10h, and the coating thickness is increased by 0.1-0.2mm/time until the kiln skin material is coated;

Description: Putting liquid kiln lining materials into the interior of the rotary kiln and preheating the hazardous waste rotary kiln can reduce the wear and corrosion of refractory materials, better control the quality and stability of the product, and increase its service life. The efficiency of the kiln lining can be ensured by adjusting the feeding amount.

Furthermore, before preheating, the interior of the hazardous waste rotary kiln is pretreated by corona treatment; the corona power is 3-5kW, and the treatment time is 15-25s;

Description: Corona treatment can remove rust on the surface of rotary kiln, enhance the wettability and adhesion of the surface. For large equipment such as rotary kiln, corona treatment can clean and remove rust on its surface, and improve the adhesion and durability of the coating.

Furthermore, the parameters of the electrostatic spraying are: voltage of 50-70 kV, current of 1-3 A, spray gun distance of 200-300 mm, and spraying speed of 10-15 m/min;

Note: Under the above parameters, electrostatic spraying can effectively ensure the powder coating rate on the inner wall of the rotary kiln, better ensure the uniformity of the coating, and improve the coverage effect of the kiln skin material.

The beneficial effects of the present invention are:

(1) The present invention has a good promoting effect on the viscosity of refractory brick kiln lining materials by adopting a viscosity-enhancing coating. Silk fibroin can improve the surface hardness and wear resistance of the kiln lining material at high temperature. The kiln lining material prepared by using modified silk fibroin-based alkyd resin as a viscosity-enhancing coating has good thermal stability and viscosity, thereby further enhancing the kiln lining ability of the kiln lining material.

(2) The present invention utilizes a fluorocarbon branched urethane oil additive to mix with an alkyd resin and ammonium polyphosphate to efficiently optimize the effect of improving the adhesion of the resin mixture to silicate minerals, while effectively improving the leveling and wettability of the kiln lining material. The cost of using a fluorocarbon branched urethane oil additive is lower than that of other modified materials. The performance of silk fibroin is utilized to further enhance the impact resistance and wear resistance of the coating, and to improve its waterproof performance and durability, thereby further improving the kiln lining performance of the kiln lining material.

(3) The present invention mixes aluminate minerals and silicate minerals with magnesium aluminum spinel respectively and then adds them in batches, which effectively improves the mixing uniformity of the mixture. At the same time, the viscosity-enhancing coating is prepared by using two parts of base materials containing modified silk fibroin-based alkyd resin and not containing modified silk fibroin-based alkyd resin, and then mixing them separately, so that the modified silk fibroin-based alkyd resin can be better dispersed in yellow clay and montmorillonite, further improving the viscosity of the kiln skin material.

DETAILED DESCRIPTION

The present invention is further described in detail below in conjunction with specific implementation methods to better reflect the advantages of the present invention.

Example 1

A high-viscosity refractory brick kiln lining material, which is composed of 47% silicate minerals, 23% paint waste, 6% magnesia-alumina spinel, 0.4% viscosity-enhancing coating and the remainder aluminate minerals by weight percentage; the particle size of the magnesia-alumina spinel is 1.5-2.5 mm, and the particle sizes of the silicate minerals and the aluminate minerals are 0.06-0.07 mm;

Among them, silicate minerals are composed of C ₃ S and C ₂ S in a mass ratio of 4:1.9;

The adhesion-enhancing coating is composed of modified silk fibroin-based alkyd resin, yellow clay, montmorillonite, and deionized water in a mass ratio of 4.8:18:6.4:23;

Magnesium-aluminum spinel is composed of Al ₂ O ₃ , ZrO ₂ ·SiO ₂ , Fe ₂ O ₃ and MgO in a mass ratio of 53:0.8:44:2.2;

Aluminate minerals are composed of C ₃ A and C ₄ AF in a mass ratio of 1:1;

The preparation method of the modified silk fibroin-based alkyd resin is as follows: 30 g of silk fibroin is added into 190 mL of acetone solvent with a mass concentration of 50% and stirred at a speed of 325 rpm for 28 minutes to obtain a silk fibroin solution; ultrasonic mixing is performed according to the weight ratio of alkyd resin: fluorocarbon branched urethane oil additive: ammonium polyphosphate of 43:13.7:13 to obtain a resin mixture;

2/3 of the silk fibroin solution is taken for later use, a resin mixture is prepared according to a weight ratio of the resin mixture to the silk fibroin solution of 9:8, and the resin mixture is added dropwise to the silk fibroin solution at a rate of 4 drops/min to obtain a mixture A; then the remaining 1/3 of the silk fibroin solution is added dropwise to the mixture A at a rate of 9 drops/min, and the mixture is mixed to obtain a modified silk fibroin-based alkyd resin;

The parameters of the ultrasonic mixing are ultrasonic frequency: 36kHz, ultrasonic time: 9min;

This embodiment also provides a method for preparing a high-viscosity refractory brick kiln lining material, comprising the following steps:

S1. Raw material preparation

S1-1, take 1/2 of the magnesium aluminum spinel and the aluminate mineral and mix them at room temperature for 40 minutes to obtain a mixture I, and mix the remaining magnesium aluminum spinel with the silicate mineral and the paint waste at room temperature for 25 minutes.

Obtain mixed material II, and divide mixed material II into 4 parts for later use;

S1-2, taking 3/4 of the yellow clay, the whole amount of montmorillonite and 1/2 of the deionized water and stirring and mixing them at 160rpm for 18min to obtain base material A; then the remaining yellow clay, the whole amount of the modified silk fibroin-based alkyd resin and the remaining deionized water were subjected to microwave treatment for 18min to obtain base material B; finally, base material B was sprayed on the surface of base material A at a rate of 40mL/min, and mixed to obtain a tackifying coating for standby use; step S1-

2, the microwave treatment parameters were: microwave irradiation intensity was 110 W, microwave irradiation temperature was 87 °C;

S2. Raw material mixing

The mixed material I obtained in step S1 is transferred to a ball mill with a rotation speed of 385 rpm. The initial temperature of the ball mill is 55°C. The temperature of the ball mill is increased at a rate of 40°C/min. After the temperature is raised to 875°C, it is kept warm for 1.7 hours. During the heating process, the mixed material II is added to the ball mill once every 25 minutes until the addition of the mixed material II is completed; during the insulation process, 18 mL of the viscosity-increasing coating is added to the ball mill every 25 minutes until the insulation treatment is completed to obtain the kiln skin material;

This embodiment also provides an application of a high-viscosity refractory brick kiln skin material, which is applied to a hazardous waste rotary kiln;

The coating method is:

First, the inner wall of the hazardous waste rotary kiln is preheated to 185°C for 0.7 hours. Then, within the first 24 hours of opening the kiln, 65% of the normal output of the hazardous waste rotary kiln is fed by electrostatic spraying, and the coating thickness is maintained at 2mm. After more than 24 hours, the coating thickness is increased by 7% every 9 hours until the kiln skin material is coated. The parameters of electrostatic spraying are: voltage 60kV, current 2A, spray gun distance 250mm, spray speed 13m/min.

Before preheating, the inside of the hazardous waste rotary kiln is pretreated by corona treatment; the corona power is 4kW and the treatment time is 20s.

Example 2

Different from Example 1, a high-viscosity refractory brick kiln lining material is composed of 40% silicate minerals, 22% paint waste, 5% magnesium aluminum spinel, 0.3% adhesion-enhancing coating and the remainder of aluminate minerals by weight percentage.

Example 3

Different from Example 1, a high-viscosity refractory brick kiln lining material is composed of 55% silicate minerals, 25% paint waste, 7% magnesium aluminum spinel, 0.5% adhesion-enhancing coating and the remainder aluminate minerals by weight percentage.

Example 4

Different from Example 1, the particle size of the magnesium-aluminum spinel is 1-1.5 mm, and the particle size of the silicate mineral and the aluminate mineral is 0.05-0.06 mm.

Example 5

Different from Example 1, the particle size of the magnesium-aluminum spinel is 2.5-3 mm, and the particle size of the silicate mineral and the aluminate mineral is 0.07-0.074 mm.

Example 6

The difference from Example 1 is that the silicate mineral is composed of C ₃ S and C ₂ S in a mass ratio of 3:1.8.

Example 7

The difference from Example 1 is that the silicate mineral is composed of C ₃ S and C ₂ S in a mass ratio of 5:2.

Example 8

Different from Example 1, the viscosity-enhancing coating is composed of modified silk fibroin-based alkyd resin, yellow clay, montmorillonite, and deionized water in a mass ratio of 3.2:17:6.2:20.

Example 9

Different from Example 1, the viscosity-enhancing coating is composed of modified silk fibroin-based alkyd resin, yellow clay, montmorillonite, and deionized water in a mass ratio of 6.4:19:6.5:25.

Example 10

Different from Example 1, the magnesia-alumina spinel is composed of Al ₂ O ₃ , ZrO ₂ ·SiO ₂ , Fe ₂ O ₃ and MgO in a mass ratio of 52.4:0.7:43:0.5.

Embodiment 11

Different from Example 1, the magnesia-alumina spinel is composed of Al ₂ O ₃ , ZrO ₂ ·SiO ₂ , Fe ₂ O ₃ and MgO in a mass ratio of 53.6:0.9:45:3.9.

Example 12

Different from Example 1, the preparation method of the modified silk fibroin-based alkyd resin is as follows: 25 g of silk fibroin is added to 180 mL of acetone solvent having a mass concentration of 48% and stirred at a speed of 300 rpm for 25 min to obtain a silk fibroin solution; ultrasonic mixing is performed according to a weight ratio of alkyd resin: fluorocarbon branched chain urethane oil additive: ammonium polyphosphate of 40:12.7:10 to obtain a resin mixture;

Take 2/3 of the silk fibroin solution for later use, prepare a resin mixture according to the weight ratio of resin mixture: silk fibroin solution of 8:7.6, and add the resin mixture dropwise into the silk fibroin solution at a rate of 3 drops/min to obtain a mixture A; then add the remaining 1/3 of the silk fibroin solution dropwise into the mixture A at a rate of 8 drops/min, and mix well to obtain a modified silk fibroin-based alkyd resin.

Example 13

Different from Example 1, the preparation method of the modified silk fibroin-based alkyd resin is as follows: 40 g of silk fibroin is added into 200 mL of acetone solvent having a mass concentration of 52% and stirred at a speed of 350 rpm for 30 min to obtain a silk fibroin solution; ultrasonic mixing is performed according to a weight ratio of alkyd resin: fluorocarbon branched chain urethane oil additive: ammonium polyphosphate of 45:14.6:15 to obtain a resin mixture;

Take 2/3 of the silk fibroin solution for later use, prepare a resin mixture according to the weight ratio of resin mixture: silk fibroin solution of 10:8.5, and add the resin mixture dropwise into the silk fibroin solution at a rate of 5 drops/min to obtain a mixture A; then add the remaining 1/3 of the silk fibroin solution dropwise into the mixture A at a rate of 10 drops/min, and mix well to obtain a modified silk fibroin-based alkyd resin.

Embodiment 14

Different from Example 1, in the preparation method of the modified silk fibroin-based alkyd resin, the parameters of ultrasonic mixing are ultrasonic frequency: 32 kHz, and ultrasonic time: 10 min.

Embodiment 15

Different from Example 1, in the preparation method of the modified silk fibroin-based alkyd resin, the parameters of ultrasonic mixing are ultrasonic frequency: 40 kHz, and ultrasonic time: 8 min.

Example 16

Different from Example 1, in a method for preparing a high-viscosity refractory brick kiln lining material,

S1. Raw material preparation

S1-1. Take 1/3 of the magnesium aluminum spinel and aluminate minerals and mix them at room temperature for 30 minutes to obtain mixture I. Mix the remaining magnesium aluminum spinel with silicate minerals and paint waste at room temperature for 20 minutes to obtain mixture II. Divide mixture II into 3 parts and set aside.

Embodiment 17

Different from Example 1, in a method for preparing a high-viscosity refractory brick kiln lining material,

S1. Raw material preparation

S1-1. Take 2/3 of the magnesium aluminum spinel and aluminate minerals and mix them at room temperature for 50 minutes to obtain mixture I. Mix the remaining magnesium aluminum spinel with silicate minerals and paint waste at room temperature for 30 minutes to obtain mixture II. Divide mixture II into 5 equal parts for later use.

Embodiment 18

Different from Example 1, in a method for preparing a high-viscosity refractory brick kiln lining material,

S1-2, take 3/4 of the yellow clay, the whole amount of montmorillonite and 1/4 of the deionized water and stir and mix them at 150rpm for 20min to obtain base material A; then microwave the remaining 1/4 of the yellow clay, the whole amount of the modified silk fibroin-based alkyd resin and the remaining deionized water for 15min to obtain base material B; finally, spray base material B on the surface of base material A at a rate of 30mL/min, mix well to obtain the viscosity-enhancing coating, and set aside.

Embodiment 19

Different from Example 1, in a method for preparing a high-viscosity refractory brick kiln lining material,

S1-2, take 3/4 of the yellow clay, the whole amount of montmorillonite and 3/4 of the water and stir and mix them at 170rpm for 15min to obtain base material A; then microwave the remaining 1/4 of the yellow clay, the whole amount of modified silk fibroin-based alkyd resin and the remaining water for 20min to obtain base material B; finally, spray base material B on the surface of base material A at a rate of 50mL/min, mix well to obtain the viscosity-enhancing coating, and set aside.

Embodiment 20

Different from Example 1, in step S1-2, the microwave treatment parameters are: microwave irradiation intensity is 100 W, and microwave irradiation temperature is 75°C.

Embodiment 21

Different from Example 1, in step S1-2, the microwave treatment parameters are: microwave irradiation intensity is 120W, and microwave irradiation temperature is 100°C.

Embodiment 22

The difference from Example 1 is that S2 and raw material mixing

The mixed material I obtained in step S1 is transferred to a ball mill with a rotation speed of 370 rpm. The initial temperature of the ball mill is 50°C, and the temperature of the ball mill is increased at a rate of 30°C/min. After the temperature is raised to 850°C, it is kept warm for 2 hours. During the heating process, the mixed material II is added to the ball mill once every 20 minutes until the addition of the mixed material II is completed; during the insulation process, 20 mL of the viscosity-increasing coating is added to the ball mill every 20 minutes until the insulation treatment is completed to obtain the kiln skin material.

Embodiment 23

The difference from Example 1 is that S2 and raw material mixing

The mixed material I obtained in step S1 is transferred to a ball mill with a rotation speed of 400 rpm. The initial temperature of the ball mill is 60°C, and the temperature of the ball mill is increased at a rate of 50°C/min. After the temperature is raised to 900°C, it is kept warm for 1.5 hours. During the heating process, the mixed material II is added to the ball mill once every 30 minutes until the addition of the mixed material II is completed; during the insulation process, 15 mL of the viscosity-increasing coating is added to the ball mill every 30 minutes until the insulation treatment is completed to obtain the kiln skin material.

Embodiment 24

Different from Example 1, the coating method of the refractory brick kiln skin material in the hazardous waste rotary kiln is:

First, preheat the inner wall of the hazardous waste rotary kiln to 180°C for 1 hour; then, within the first 24 hours of opening the kiln, feed 60% of the normal output of the hazardous waste rotary kiln by electrostatic spraying, and keep the coating thickness at 1mm; after more than 24 hours, adjust the feeding amount by 5% every 8 hours, and adjust the coating thickness by 0.1mm/time.

Embodiment 25

Different from Example 1, the coating method of the refractory brick kiln skin material in the hazardous waste rotary kiln is:

First, preheat the inner wall of the hazardous waste rotary kiln to 190°C for 1 hour; then, within the first 24 hours of opening the kiln, feed 70% of the normal output of the hazardous waste rotary kiln by electrostatic spraying, and keep the coating thickness at 3mm; after more than 24 hours, adjust the feeding amount by increasing by 10% every 10 hours, and adjust the coating thickness by 0.2mm/time.

Embodiment 26

Different from Example 1, the parameters of electrostatic spraying are: voltage of 50 kV, current of 1 A, spray gun distance of 200 mm, and spraying speed of 10 m/min.

Embodiment 27

Different from Example 1, the parameters of the electrostatic spraying are: voltage of 70 kV, current of 3 A, spray gun distance of 300 mm, and spraying speed of 15 m/min.

Embodiment 28

Different from Example 1, before preheating, the interior of the hazardous waste rotary kiln is pretreated by corona treatment; the corona power is 3 kW and the treatment time is 25 s.

Embodiment 29

Different from Example 1, before preheating, the interior of the hazardous waste rotary kiln is pretreated by corona treatment; the corona power is 5 kW and the treatment time is 15 s.

Experimental example

For the refractory brick kiln lining material of each embodiment, 5 samples of each embodiment were taken to test the bonding performance of the material. The test results of the 5 samples of each embodiment were averaged as the test results of the embodiment. The specific exploration is as follows:

1. The influence of the proportion of refractory brick kiln lining materials on the performance of refractory brick kiln lining materials.

Table 1 Thermal insulation properties and bonding properties (1600°C) of refractory brick kiln lining materials in Examples 1 to 11 and Comparative Examples 1 to 2

Comparative Example 1: Different from Example 1, no viscosity-enhancing coating was added.

Control Example 2: Different from Example 1, no modified silk fibroin-based alkyd resin was added.

Conclusion: From the data comparison of Examples 1 to 3 and Control Example 1 in Table 1, it can be seen that the lack of the addition of a thickening coating will cause a significant decrease in the viscosity of the refractory brick kiln lining material. At the same time, due to the lack of the addition of yellow clay and montmorillonite, the stability effect and viscosity of the protective layer formed by the kiln lining are affected, thereby further affecting the thermal insulation effect of the kiln lining material; and from the data comparison of Examples 1, 8 to 9 and Control Examples 1 to 2, it can be seen that the addition of yellow clay and montmorillonite can promote the viscosity of the kiln lining material to a certain extent, but the viscosity of the kiln lining material prepared without modified silk fibroin-based alkyd resin is still far inferior to that of the kiln lining material prepared in Examples 1 and 8 to 9, and the thermal insulation performance of the kiln lining material prepared without modified silk fibroin-based alkyd resin in Control Example 2 is also significantly deteriorated. This is because the kiln lining material prepared using the modified silk fibroin-based alkyd resin as a thickening coating not only has good thermal stability, but also further enhances the kiln lining ability of the kiln lining material, that is, the adhesion; Therefore, considering all factors, Example 1 is the best solution.

2. To explore the effect of the preparation method of modified silk fibroin-based alkyd resin and the preparation method of high-viscosity refractory brick kiln cladding material on the performance of refractory brick kiln cladding material

Table 2 Thermal insulation properties and bonding properties (1600°C) of refractory brick kiln lining materials in Examples 1, 12 to 23 and Comparative Examples 3 to 4

Control Example 3: Different from Example 1, in the preparation method of the modified silk fibroin-based alkyd resin, the alkyd resin is not treated with a fluorocarbon branched chain urethane oil additive.

Control Example 4: Different from Example 1, in the preparation method of the modified silk fibroin-based alkyd resin, the resin mixture and the silk fibroin solution are mixed by directly adding the mixture A dropwise into the silk fibroin solution.

Control Example 5: Different from Example 1, in step S1-2, yellow clay, montmorillonite, modified silk fibroin-based alkyd resin and deionized water are directly mixed under an ultrasonic environment.

Comparative Example 6: Different from Example 1, in step S2, there is no restriction on the adding method of mixed material II and the viscosity-enhancing coating, and the mixing is completed directly during the heating process.

Conclusion: From the data comparison of Example 1, Examples 12-13 and Control Example 3, it can be seen that the lack of the fluorocarbon branched urethane oil additive for the alkyd resin treatment step will cause the thermal insulation and bonding properties of the kiln lining material to be significantly reduced. This is because the lack of the modification effect of the fluorocarbon branched urethane oil additive on the alkyd resin reduces the adhesion, leveling and wettability of the coating, thereby affecting the effect of the tackifying coating on silicate minerals, thereby reducing the stability of the kiln lining material and further affecting the thermal insulation performance of the kiln lining material; From the data comparison of Table 1, Examples 12-13 and Control Example 4, it can be seen that directly adding the mixed solution A to the silk fibroin solution can fully exert the fluorocarbon branched urethane oil additive. The carbon-branched urethane oil additive has a modifying effect on the alkyd resin, but has a smaller effect on the stability of the tackifying coating, resulting in a weakened thermal insulation performance of the kiln lining material in Control Example 4; it can be seen from the data in Table 1, Examples 18 to 19 and Control Example 5 that the thermal insulation and bonding properties of the kiln lining material obtained in Control Example 5 are slightly weakened. This is because the base material A and base material B are not processed in batches, resulting in uneven mixing of the components of the tackifying filler, thereby affecting the various properties of the kiln lining material; from the comparison of the data in Examples 1, 22 to 23 and Control Example 6, it can be seen that the material performance of the kiln lining is reduced if the mixed material II and the tackifying coating are not mixed in batches, thus, Example 1 is the optimal solution.

3. Explore the influence of coating method on the performance of refractory brick kiln lining

Table 3 Thermal insulation and bonding properties of refractory brick kiln skin in Examples 1, 24-25, 28-29 and Comparative Examples 7-8 (1600°C)

Comparative Example 7: Different from Example 1, in the method for coating the refractory brick kiln lining material in the hazardous waste rotary kiln, the inner wall of the hazardous waste rotary kiln is not preheated.

Comparative Example 8: Different from Example 1, in the coating method of the refractory brick kiln lining material in the hazardous waste rotary kiln, no corona treatment is performed before preheating.

Conclusion: It can be seen from the data in Table 3 that the lack of preheating treatment or corona treatment before preheating will lead to the deterioration of the performance of the kiln lining material. Preheating the hazardous waste rotary kiln can reduce the wear and corrosion of the refractory material and better improve the quality and stability of the kiln lining material. Corona treatment can clean and remove rust on the surface, improve the adhesion and durability of the kiln lining material, thereby further improving the performance impact on the hazardous waste rotary kiln. Based on this, Example 1 is still selected as the optimal solution.

Claims (9)

1. A high-viscosity refractory brick kiln lining material, characterized in that, by weight percentage, it is composed of 40-55% silicate minerals, 22-25% paint waste, 5-7% magnesia-alumina spinel, 0.3-0.5% adhesion-enhancing coating and the balance aluminate minerals; Wherein, the silicate mineral is composed of C ₃ S and C ₂ S in a mass ratio of 3-5:1.8-2; The viscosity-enhancing coating is composed of modified silk fibroin-based alkyd resin, yellow clay, montmorillonite, and deionized water in a mass ratio of 3.2-6.4:17-19:6.2-6.5:20-25; The magnesium aluminum spinel is composed of Al ₂ O ₃ , ZrO ₂ ·SiO ₂ , Fe ₂ O ₃ and MgO in a mass ratio of 52.4-53.6: 0.7-0.9: 43-45: 0.5-3.9; The aluminate mineral is composed of C ₃ A and C ₄ AF in a mass ratio of 1:1. 2. A high-viscosity refractory brick kiln lining material as claimed in claim 1, characterized in that the preparation method of the modified silk fibroin-based alkyd resin is as follows: 25 to 40 g of silk fibroin is added to 180 to 200 mL of acetone solvent with a mass concentration of 48 to 52% and stirred at a speed of 300 to 350 rpm for 25 to 30 minutes to obtain a silk fibroin solution; ultrasonic mixing is performed according to the weight ratio of alkyd resin: fluorocarbon branched urethane oil additive: ammonium polyphosphate of 40 to 45:12.7 to 14.6:10 to 15 to obtain a resin mixture; 2/3 of the silk fibroin solution is taken for later use, a resin mixture is prepared according to a weight ratio of resin mixture: silk fibroin solution of 8-10:7.6-8.5, and the resin mixture is added dropwise to the silk fibroin solution at a rate of 3-5 drops/min to obtain a mixture A; then the remaining 1/3 of the silk fibroin solution is added dropwise to the mixture A at a rate of 8-10 drops/min, and mixed to obtain a modified silk fibroin-based alkyd resin; The parameters of the ultrasonic mixing are ultrasonic frequency: 32-40 kHz, and ultrasonic time: 8-10 min. 3. A high-viscosity refractory brick kiln lining material as described in claim 1, characterized in that the particle size of the magnesia-alumina spinel is 1 to 3 mm, and the particle size of the silicate mineral and the aluminate mineral is 0.05 to 0.074 mm. 4. A method for preparing a high-viscosity refractory brick kiln lining material, based on a high-viscosity refractory brick kiln lining material according to any one of claims 1 to 3, characterized in that it comprises the following steps: S1. Raw material preparation S1-1, take 1/3 to 2/3 of the magnesium aluminum spinel and the aluminate mineral and mix them at room temperature for 30 to 50 minutes to obtain a mixture I, and mix the remaining magnesium aluminum spinel with silicate minerals and paint waste at room temperature for 20 to 30 minutes to obtain a mixture II, and divide the mixture II into 3 to 5 portions for standby use; S1-2, take 3/4 of the yellow clay, the whole amount of montmorillonite and 1/4 to 3/4 of deionized water and stir and mix them at 150 to 170 rpm for 15 to 20 minutes to obtain base material A; then microwave the remaining yellow clay, the whole amount of modified silk fibroin-based alkyd resin and the remaining deionized water for 15 to 20 minutes to obtain base material B; finally, spray the base material B on the surface of the base material A at a rate of 30 to 50 mL/min, mix well to obtain a tackifying coating, and set aside; S2. Raw material mixing The mixed material I obtained in step S1 is transferred to a ball mill with a rotation speed of 370-400rpm, the initial temperature of the ball mill is 50-60°C, the temperature of the ball mill is increased at a rate of 3-5°C/min, and the temperature is raised to 85-90°C and then kept warm for 1.5-2h. During the heating process, the mixed material II is added to the ball mill once every 20-30min until the addition of the mixed material II is completed; during the insulation process, 15-20mL of the viscosity-increasing coating is added to the ball mill every 20-30min until the insulation treatment is completed to obtain the kiln skin material. 5. The method for preparing a high-viscosity refractory brick kiln lining material as described in claim 4 is characterized in that in step S1-2, the microwave treatment parameters are: microwave irradiation intensity is 100-120W, and microwave irradiation temperature is 75-100°C. 6. The use of a high-viscosity refractory brick kiln lining material as described in any one of claims 1 to 3, characterized in that it is used for coating on a hazardous waste rotary kiln. 7. The application of a high-viscosity refractory brick kiln lining material according to claim 6, characterized in that the coating method is: First, the inner wall of the hazardous waste rotary kiln is preheated to 180-190°C for 0.5-1h; then, within the first 24h of opening the kiln, 60-70% of the normal output of the hazardous waste rotary kiln is fed by electrostatic spraying, and the coating thickness is maintained at 1-3mm; after more than 24h, the feeding amount is adjusted by increasing 5-10% every 8-10h, and the coating thickness is increased by 0.1-0.2mm/time until the kiln skin material is coated. 8. The use of a high-viscosity refractory brick kiln lining material as described in claim 7 is characterized in that before preheating, the interior of the hazardous waste rotary kiln is pretreated by corona treatment; the corona power is 3 to 5 kW, and the treatment time is 15 to 25 seconds. 9. The use of a high-viscosity refractory brick kiln lining material as described in claim 8 is characterized in that the parameters of the electrostatic spraying are: voltage of 50-70 kV, current of 1-3 A, spray gun distance of 200-300 mm, and spraying speed of 10-15 m/min.