Production method of high-strength carbon black

Abstract

The invention belongs to the field of carbon black preparation, and particularly relates to a production method of high-strength carbon black. In order to solve the problem that in the prior art, the reinforcing performance of carbon black cannot reach an ideal state due to the fact that the particle size of the carbon black is not uniform and aggregate distribution is not concentrated, the invention provides the production method of the high-strength carbon black, a reactor adopted by the method is a horizontal reactor, the reactor comprises a heating area and a reaction area, and the reaction area is provided with two conical pipelines; the two reducing ends of the conical pipeline are communicated, so that the reaction is promoted to be more thorough, and carbon black with more uniform particle size is generated. The anthracene oil and the coal tar are mixed to ensure that the process oil has ideal physical and chemical properties such as density, viscosity, moisture content and the like, so that not only is more uniform carbon black particles favorably formed, but also the reinforcing performance of the carbon black particles can be improved, and the consistency and stability of conditions in the reaction process can be ensured, thereby improving the quality of a carbon black product.

Description

Technical Field

[0001] The present invention relates to the field of carbon black preparation, and in particular to a method for producing high-strength carbon black. Background Art

[0002] With the advancement of modern engineering technology, and the increasing performance requirements for engineering rubber products, particularly in industries like rail transit and construction, the demand for carbon black, a key filler, has become increasingly stringent. Carbon black, as a key additive in rubber products, is primarily used to enhance the mechanical strength of rubber, such as tensile strength and abrasion resistance. However, current carbon black products on the market still face numerous challenges in meeting these high-performance requirements. In the rail transit sector in particular, shock-absorbing products must not only exhibit high resilience to absorb vibration energy but also possess sufficient strength to ensure long-term reliability. Similarly, in the construction industry, waterproof products must not only possess excellent waterproof properties but also high strength to withstand various harsh environmental conditions. Furthermore, high-pressure hose applications require them to withstand extremely high burst pressures, placing even higher standards on carbon black's reinforcing properties. Unfortunately, despite significant progress in the domestic carbon black industry over the past few decades, significant lags remain in high-end applications compared to advanced international standards.

[0003] The existing carbon black production processes and technical solutions have, to a certain extent, limited the further improvement of carbon black quality. The existing process is limited by the design of traditional carbon black production equipment and its process flow. The aggregate distribution of carbon black particles is often not concentrated enough, resulting in its reinforcement properties not being able to reach the ideal state. This directly affects the final performance of rubber products produced using this type of carbon black, especially when facing the high-demand application scenarios mentioned above. The structural design of traditional carbon black production equipment has failed to fully consider how to optimize the reaction conditions to obtain a more uniform carbon black particle size; the lack of refined control in the selection and processing of raw materials makes it difficult to ensure the quality and consistency of each batch of products, affecting the production efficiency and quality of carbon black. Summary of the Invention

[0004] In order to solve the problem in the prior art that the carbon black particle size is uneven and the aggregate distribution is not concentrated, resulting in its reinforcement performance being unable to reach an ideal state, the present application provides a method for producing high-strength carbon black. The reactor used in the method is a horizontal reactor. The reactor includes a heating zone and a reaction zone. The reaction zone is provided with two conical pipes, and the two reduced-diameter ends of the conical pipes are connected to promote a more thorough reaction and generate carbon black with a more uniform particle size.

[0005] The present application provides a method for producing high-strength carbon black, comprising the following steps:

[0006] S1. Mixing anthracene oil and coal tar to obtain a uniform process oil;

[0007] S2, preheat the reactor and the process oil obtained in S1, and spray the preheated process oil into the reactor using an axial oil gun;

[0008] S3, the process oil is thermally cracked in the reactor, and a quenching water gun is inserted in the cooling section to spray cooling water to lower the temperature and terminate the reaction;

[0009] S4. The powdered carbon black is collected by a bag filter, crushed by a micron grinder, and then transported to a granulator for granulation. The final product is obtained by drying, screening, and magnetic separation.

[0010] Furthermore, the mass ratio of anthracene oil to coal tar in step S1 is 3:2.

[0011] Furthermore, the density ρ20 of the process oil in step S1 is 1.16-1.2 g / cm 3 , viscosity E80≤3.0, moisture ≤0.5%, ash ≤0.08%, toluene insoluble matter ≤1.0%, distillate before 360℃ ≥50%.

[0012] Furthermore, in step S2, the preheating reactor is preheated by introducing air into the reactor through the upper and lower hot air pipes of the reactor, and the air temperature is 630-730 ° C and the flow rate is 14500-16000 Nm 3 / h.

[0013] Furthermore, in step S2, the process oil preheated to 180-200°C is sprayed into the reactor through an axial oil gun. The angle of the oil gun head is 80-100 degrees, and the process oil is sprayed out in a spray form. The injection process oil flow rate is 4500-5500kg / h and the injection pressure is 2.5-3.5Mpa.

[0014] Furthermore, in step S3, four quenching water guns are inserted into the cooling section. The quenching water guns are distributed in two rows, front and back, with two in each row. The distances between the two rows of quenching water guns and the reactor are 13 meters and 15 meters respectively.

[0015] Furthermore, the reactor is a horizontal reactor, which is connected to the cooling section. The reactor includes a heating zone and a reaction zone. The upper and lower parts of the heating zone are provided with hot air ducts. The reaction zone is provided with two conical pipes, and the two reduced diameter ends of the conical pipes are connected.

[0016] Furthermore, the diameter of the connecting position of the two tapered pipes in the reaction zone is 550-600 mm.

[0017] Furthermore, the inner wall of the reactor is made of refractory bricks.

[0018] The present invention provides a method for producing high-strength carbon black. Anthracene oil and coal tar are mixed in a mass ratio of 3:2. Through rigorous filtration and mixing processes, the process oil is ensured to have ideal physical and chemical properties, such as density, viscosity, and moisture content. This not only helps form more uniform carbon black particles, but also improves their reinforcing properties. It also ensures consistency and stability of reaction conditions, thereby improving the quality and consistency of the carbon black product. Furthermore, low ash content and controlled toluene-insoluble matter content also help reduce impurities and ensure the purity of the carbon black.

[0019] The process of preheating the reactor and process oil is to ensure that the raw materials reach the best condition before entering the reaction zone. The air is preheated by the air preheater and then passed into the reactor. The temperature is maintained at 630-730℃ and the flow rate is controlled at 14500-16000Nm 3 / h, while simultaneously preheating the process oil to 180-200°C and spraying it into the reactor via an axial oil gun. This method allows the process oil to undergo a rapid cracking reaction at high temperatures. Adjusting the angle of the oil gun and controlling the injection pressure distributes the process oil in a spray-like manner, increasing its contact area with the high-temperature air, promoting a more thorough reaction, and producing carbon black with a more uniform particle size. This design results in a more uniform primary carbon black particle size, improving its reinforcing properties.

[0020] Inserting quenching water jets into the cooling section to lower the temperature and terminate the reaction effectively halts the reaction process, preventing excessive growth or morphological changes in the carbon black particles. Proper placement of the quenching water jets allows for precise control of the cooling rate, which is crucial for maintaining the ideal size and morphology of the carbon black particles. This approach not only improves production efficiency but also reduces unnecessary energy consumption.

[0021] Powdered carbon black is collected using a bag filter, crushed in a micron grinder, and then transported to a pelletizer for granulation. Finally, the final product undergoes drying, screening, and magnetic separation. These processing steps not only help remove impurities but also adjust the physical properties of the carbon black, making it more suitable for various applications. This method can significantly improve the applicability and market competitiveness of carbon black, especially for applications requiring high-performance carbon black, such as vibration damping and water-blocking products in the rail transit and construction industries.

[0022] Regarding the design of the reactor, this application adopts a horizontal structure and is equipped with upper and lower hot air ducts in the heating zone. The reaction zone is provided with two tapered pipes, and the two reduced diameter ends of the tapered pipes are connected. This design is conducive to enhancing the mixing effect between the reactants, making the reaction more complete and the carbon black primary particle size more uniform. The inner wall of the reactor is made of refractory brick material, which can withstand high temperatures of up to 2000°C, ensuring the safe and stable operation of the equipment, while also supporting efficient production. Therefore, this design can effectively solve the problem of insufficient reinforcement performance caused by the non-concentrated distribution of carbon black aggregates in the prior art.

[0023] This application significantly improves the performance indicators of carbon black by optimizing the raw material formula, improving the reactor design and fine-tuning the production process parameters, such as a higher specific surface area and a more concentrated aggregate distribution, which significantly improves the tensile strength of the compounded rubber and meets the requirements of the application scenario for high-strength carbon black. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 The figure is a process flow chart of the production method of high-strength carbon black.

[0025] Figure 2 Schematic diagram of the reactor structure.

[0026] Figure 3 This is the aggregate distribution diagram of the carbon black obtained in Example 1 of the present application.

[0027] In the figure: 1, reactor; 2, hot air duct; 3, cold section; 4, rapid cooling water gun; 101, heating zone; 102, reaction zone. DETAILED DESCRIPTION

[0028] The present application provides a method for producing high-strength carbon black, such as Figure 1-Figure 2 As shown, the method adopts a horizontal reactor 1, which is connected to a cooling section 3. The reactor 1 includes a heating zone 101 and a reaction zone 102. A hot air duct 2 is provided at the upper and lower parts of the heating zone 101. The reaction zone 102 is provided with two tapered pipes, and the two reduced diameter ends of the tapered pipes are connected. The diameter of the two tapered pipes in the reaction zone 102 is 550-600 mm. The inner wall of the reactor 1 is refractory bricks.

[0029] Example 1

[0030] S1. This application uses a horizontal reactor. The diameter of the connecting pipe between the two tapered pipes in the reaction zone is 600 mm. Anthracene oil and coal tar are selected as raw materials for mixing. The two oils are filtered and mixed in a fixed mass ratio of 3:2 to obtain a uniform process oil. The process oil's indicators meet the following standards: density ρ20 is 1.16-1.2 g / cm 3, viscosity E80≤3.0, moisture ≤0.5%, ash ≤0.08%, toluene insoluble matter ≤1.0%, distillate before 360℃ ≥50%.

[0031] S2, the air preheated by the air preheater is introduced into the reactor through the upper and lower hot air pipes of the reactor, the temperature is 650℃, the flow rate is 14500Nm 3 / h; the process oil preheated to 180°C is sprayed into the reactor through an axial oil gun. The angle of the oil gun head is 80 degrees, so that the process oil is sprayed out in a spray form, ensuring that the process oil reacts thoroughly and the generated carbon black particle size is more uniform. The injection process oil flow rate is 4500kg / h and the injection pressure is controlled at 3.5Mpa.

[0032] In the cooling section, four quenching water guns are installed to spray cooling water to lower the temperature and terminate the reaction. The quenching water guns are arranged in two rows, 13 meters and 15 meters away from the reactor, respectively.

[0033] S4. Use a bag filter to collect powdered carbon black, and use a micron grinder to crush large particles, then transport them to a granulator for granulation, and finally obtain the final product through drying, screening, and magnetic separation.

[0034] Example 2

[0035] S1. A horizontal reactor was used, and the diameter of the connecting pipe between the two tapered pipes in the reaction zone was 600 mm. Anthracene oil and coal tar were selected as raw materials for mixing. After filtering the two oils, they were mixed in a fixed mass ratio of 3:2 to obtain a uniform process oil. The process oil's indicators met the following standards: density ρ20 of 1.16-1.2 g / cm 3 , viscosity E80≤3.0, moisture ≤0.5%, ash ≤0.08%, toluene insoluble matter ≤1.0%, distillate before 360℃ ≥50%.

[0036] S2, the air preheated by the air preheater is introduced into the reactor through the upper and lower hot air pipes of the reactor, the temperature is 700℃, the flow rate is 15500Nm 3 / h; the process oil preheated to 200 ° C is sprayed into the reactor through an axial oil gun. The angle of the oil gun head is 100 degrees, so that the process oil is sprayed out in a spray form, ensuring that the process oil reacts thoroughly and the generated carbon black particle size is more uniform. The injection process oil flow rate is 5000kg / h and the injection pressure is controlled at 2.5Mpa.

[0037] In the cooling section, four quenching water guns are installed to spray cooling water to lower the temperature and terminate the reaction. The quenching water guns are arranged in two rows, 12 meters and 14 meters away from the reactor, respectively.

[0038] S4. Use a bag filter to collect powdered carbon black, and use a micron grinder to crush large particles, then transport them to a granulator for granulation, and finally obtain the final product through drying, screening, and magnetic separation.

[0039] Example 3

[0040] S1. A horizontal reactor was used, and the diameter of the connecting pipe between the two tapered pipes in the reaction zone was 550 mm. Anthracene oil and coal tar were selected as raw materials for mixing. After filtering the two oils, they were mixed in a fixed mass ratio of 3:2 to obtain a uniform process oil. The process oil's indicators met the following standards: density ρ20 of 1.16-1.2 g / cm 3 , viscosity E80≤3.0, moisture ≤0.5%, ash ≤0.08%, toluene insoluble matter ≤1.0%, distillate before 360℃ ≥50%.

[0041] S2, the air preheated by the air preheater is introduced into the reactor through the upper and lower hot air pipes of the reactor, the temperature is 730℃, the flow rate is 16000Nm 3 / h; the process oil preheated to 200 ° C is sprayed into the reactor through an axial oil gun. The angle of the oil gun head is 90 degrees, so that the process oil is sprayed out in a spray form, ensuring that the process oil reacts thoroughly and the generated carbon black particle size is more uniform. The injection process oil flow rate is 4800kg / h and the injection pressure is controlled at 3.0Mpa.

[0042] In the cooling section, four quenching water guns are installed to spray cooling water to lower the temperature and terminate the reaction. The quenching water guns are arranged in two rows, 14 meters and 16 meters away from the reactor, respectively.

[0043] S4. Use a bag filter to collect powdered carbon black, and use a micron grinder to crush large particles, then transport them to a granulator for granulation, and finally obtain the final product through drying, screening, and magnetic separation.

[0044] The reactor used in the comparative example is a horizontal reactor, the diameter of the pipe at the connecting position of the two tapered pipes in the reaction zone is 700 mm, the oil gun head angle used is 60-75 degrees, the cooling water guns are in a row, and the distance from the reactor is 17 meters. The rest is the same as Example 1.

[0045] The products obtained from the embodiments and comparative examples were tested. Figure 3 As shown, the carbon black obtained in the examples of the present application has a more concentrated aggregate distribution compared with the carbon black obtained in the comparative examples.

[0046]

[0047] The products obtained in Examples and Comparative Examples were used as raw materials and plasticized in an internal mixer according to the following formula for 2 minutes. The top bolt was raised and the material was swept after 6 minutes. The internal mixing was completed after 8 minutes. The rubber mixture was then rolled 3 times on an open mixer and sheeted.

[0048]

[0049]

[0050] The obtained rubber compound was subjected to performance tests, and the obtained data are shown in the following table.

[0051] Mooney viscosity Tensile strength MPa Elongation at break % Compound hardness Example 1 62.51 12.83 195.83 75 Example 2 62.85 13.10 195.27 75 Example 3 61.63 12.94 196.82 75 Comparative Example 61.01 11.09 192.56 74

Claims

1. A method for producing high-strength carbon black, characterized in that: The following steps are involved: S1. Mixing anthracene oil and coal tar to obtain a uniform process oil; S2, preheating the process oil obtained from the reactor (1) and S1, and spraying the preheated process oil into the reactor (1) using an axial oil gun; S3, the process oil is thermally cracked in the reactor (1), and a quenching water gun (4) is inserted into the cooling section (3) to spray cooling water to lower the temperature and terminate the reaction; S4. The powdered carbon black is collected by a bag filter, crushed by a micron grinder, and then transported to a granulator for granulation. The final product is obtained by drying, screening, and magnetic separation.

2. The method for producing high-strength carbon black according to claim 1, wherein: The mass ratio of anthracene oil to coal tar in step S1 is 3:1-2.

3. The method for producing high-strength carbon black according to claim 1, characterized in that: The density ρ20 of the process oil in step S1 is 1.16-1.2 g / cm 3 , viscosity E80≤3.0, moisture ≤0.5%, ash ≤0.08%, toluene insoluble matter ≤1.0%, distillate before 360℃ ≥50%.

4. The method for producing high-strength carbon black according to claim 1, wherein: In step S2, the preheating reactor (1) is to introduce air preheated by an air preheater into the reactor (1) through the upper and lower hot air pipes of the reactor (1). The air temperature is 630-730°C and the flow rate is 14500-16000Nm 3 / h.

5. The method for producing high-strength carbon black according to claim 1, characterized in that: In step S2, the process oil preheated to 180-200°C is sprayed into the reactor (1) through an axial oil gun. The angle of the oil gun head is 80-100°C. The process oil is sprayed out in a spray form. The injection process oil flow rate is 4500-5500 kg / h and the injection pressure is 2.5-3.5 MPa.

6. The method for producing high-strength carbon black according to claim 1, characterized in that: In step S3, four quenching water guns (4) are inserted into the cooling section (3). The quenching water guns (4) are distributed in two rows, front and back, with two in each row. The distances between the two rows of quenching water guns (4) and the reactor (1) are 12-14 meters and 14-16 meters respectively.

7. The method for producing high-strength carbon black according to claim 1, characterized in that: The reactor (1) is a horizontal reactor (1), which is connected to a cooling section (3). The reactor (1) comprises a heating zone (101) and a reaction zone (102). The upper and lower parts of the heating zone (101) are provided with hot air ducts (2), and the reaction zone (102) is provided with two tapered ducts, and the two reduced diameter ends of the tapered ducts are connected.

8. The method for producing high-strength carbon black according to claim 7, characterized in that: The diameter of the connection position between the two tapered pipes in the reaction zone (102) is 550-600 mm.

9. The method for producing high-strength carbon black according to claim 7, characterized in that: The inner wall of the reactor (1) is made of refractory bricks.

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